Номер 773, страница 218 - гдз по алгебре 9 класс учебник Солтан, Солтан

Алгебра, 9 класс Учебник, авторы: Солтан Генадий Николаевич, Солтан Алла Евгеньевна, Жумадилова Аманбала Жумадиловна, издательство Кокшетау, Алматы, 2019

Авторы: Солтан Г. Н., Солтан А. Е., Жумадилова А. Ж.

Тип: Учебник

Издательство: Кокшетау

Год издания: 2019 - 2026

ISBN: 978-601-317-424-2

Рекомендовано Министерством образования и науки Республики Казахстан

IV. Тригонометрия. 29. Преобразование произведения тригонометрических функций в сумму и разность - номер 773, страница 218.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
  #connection: "mysql"
  #table: "tasks"
  #primaryKey: "id"
  #keyType: "int"
  +incrementing: true
  #with: []
  #withCount: []
  +preventsLazyLoading: false
  #perPage: 15
  +exists: true
  +wasRecentlyCreated: false
  #escapeWhenCastingToString: false
  #attributes: array:24 [
    "id" => 1108516
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "218"
    "field_page_end" => null
    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-773"
    "field_display_title" => "773"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037
      #items: array:1 [
        0 => App\Models\Term {#1036
          #connection: "mysql"
          #table: "terms"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #original: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "field_metatags_title" => null
    "field_metatags_description" => null
    "field_h1" => null
    "field_description_top" => null
    "field_description_bottom" => null
    "field_match" => null
    "breadcrumbs" => []
    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1035
      #items: []
      #escapeWhenCastingToString: false
    }
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1071
      #items: array:1 [
        0 => App\Models\Branch {#1034
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1107662
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "IV. Тригонометрия"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1039
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "147"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1038
              #items: array:1 [
                0 => App\Models\Book {#1040
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1041 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1043 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1045 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1047 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1051 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1052 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1054 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1056 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1058 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1059 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1060 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1061 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1062 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1063 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1064 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1065 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1066 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1067 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #original: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1041 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1043 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1045 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1047 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1051 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1052 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1054 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1056 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1058 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1059 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1060 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1061 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1062 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1063 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1064 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1065 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1066 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1067 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1068
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1107662
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "IV. Тригонометрия"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1039}
            "field_page_start" => "147"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1038}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1068}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1138
      #items: array:2 [
        0 => App\Models\Branch {#1069
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1107662
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "IV. Тригонометрия"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1072
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "147"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1070
              #items: array:1 [
                0 => App\Models\Book {#1073
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1074 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1076 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1078 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1080 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1084 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1085 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1087 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1089 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1091 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1092 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1093 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1094 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1095 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1096 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1097 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1098 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1100 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #original: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1074 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1076 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1078 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1080 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1084 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1085 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1087 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1089 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1091 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1092 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1093 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1094 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1095 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1096 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1097 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1098 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1100 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1101
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1107662
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "IV. Тригонометрия"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1072}
            "field_page_start" => "147"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1070}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1101}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1102
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1107671
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "29. Преобразование произведения тригонометрических функций в сумму и разность"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1103
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "216"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1104
              #items: array:1 [
                0 => App\Models\Book {#1105
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1106 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1108 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1110 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1112 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1116 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1117 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1119 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1121 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1123 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1124 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1125 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1126 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1127 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1128 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1129 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1130 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1131 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1132 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #original: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1106 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1108 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1110 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1112 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1116 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1117 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1119 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1121 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1123 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1124 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1125 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1126 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1127 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1128 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1129 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1130 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1131 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1132 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1133
              #items: array:1 [
                0 => App\Models\Branch {#1134
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1107662
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "IV. Тригонометрия"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1135 …2}
                    "field_page_start" => "147"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1136 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1137 …2}
                  ]
                  #original: array:24 [
                    "id" => 1107662
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "IV. Тригонометрия"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1135 …2}
                    "field_page_start" => "147"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1136 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1137 …2}
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1107671
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "29. Преобразование произведения тригонометрических функций в сумму и разность"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1103}
            "field_page_start" => "216"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1104}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1133}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1148
      #items: array:3 [
        0 => App\Models\Element {#1158
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1277128
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1167
              #items: array:1 [
                0 => App\Models\Edition {#1159
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 4953
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1161 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "pasha"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1162 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1163 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1164 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 4953
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1161 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "pasha"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1162 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1163 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1164 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1108516"
              "type" => "task"
            ]
            "text" => "<p><strong>773.</strong> Найдите значение выражения:</p><p><strong>a)</strong> $ \cos 8\alpha - \cos 6\alpha - 2\cos 5\alpha \cdot \cos 3\alpha, \text{ если } \cos \alpha = -\frac{1}{\sqrt{3}}; $</p><p><strong>б)</strong> $ \sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha, \text{ если } \sin \alpha = -\frac{1}{\sqrt{3}}; $</p><p><strong>в)</strong> $ \cos 7\alpha \cdot \cos 4\alpha - \cos 8\alpha \cdot \cos 3\alpha, \text{ если } \cos \alpha = \frac{\sqrt{3}}{3}; $</p><p><strong>г)</strong> $ \sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha, \text{ если } \sin \alpha = \frac{\sqrt{5}}{4}. $</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "773-1.jpg"
                "alt" => null
                "width" => "1341"
                "height" => 666
                "path" => "/media/algebra_09/soltan-u19/0-1/773-1.webp?ts=1752834761"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1277128
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1167}
            "task" => array:2 [
              "refs" => "1108516"
              "type" => "task"
            ]
            "text" => "<p><strong>773.</strong> Найдите значение выражения:</p><p><strong>a)</strong> $ \cos 8\alpha - \cos 6\alpha - 2\cos 5\alpha \cdot \cos 3\alpha, \text{ если } \cos \alpha = -\frac{1}{\sqrt{3}}; $</p><p><strong>б)</strong> $ \sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha, \text{ если } \sin \alpha = -\frac{1}{\sqrt{3}}; $</p><p><strong>в)</strong> $ \cos 7\alpha \cdot \cos 4\alpha - \cos 8\alpha \cdot \cos 3\alpha, \text{ если } \cos \alpha = \frac{\sqrt{3}}{3}; $</p><p><strong>г)</strong> $ \sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha, \text{ если } \sin \alpha = \frac{\sqrt{5}}{4}. $</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "773-1.jpg"
                "alt" => null
                "width" => "1341"
                "height" => 666
                "path" => "/media/algebra_09/soltan-u19/0-1/773-1.webp?ts=1752834761"
              ]
            ]
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1165
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1278419
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1175
              #items: array:1 [
                0 => App\Models\Edition {#1166
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 4954
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1169 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "image"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Неизвестный"
                    "field_moderator" => "pasha"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1171 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1172 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 4954
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1169 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "image"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Неизвестный"
                    "field_moderator" => "pasha"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1171 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1172 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1108516"
              "type" => "task"
            ]
            "img" => array:3 [
              0 => array:5 [
                "name" => "773-1.jpg"
                "alt" => null
                "width" => "1361"
                "height" => 833
                "path" => "/media/algebra_09/soltan-u19/1-1/773-1.webp?ts=1752831566"
              ]
              1 => array:5 [
                "name" => "773-2.jpg"
                "alt" => null
                "width" => "1418"
                "height" => 2414
                "path" => "/media/algebra_09/soltan-u19/1-1/773-2.webp?ts=1752831566"
              ]
              2 => array:5 [
                "name" => "773-3.jpg"
                "alt" => null
                "width" => "1358"
                "height" => 1447
                "path" => "/media/algebra_09/soltan-u19/1-1/773-3.webp?ts=1752831566"
              ]
            ]
          ]
          #original: array:6 [
            "id" => 1278419
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1175}
            "task" => array:2 [
              "refs" => "1108516"
              "type" => "task"
            ]
            "img" => array:3 [
              0 => array:5 [
                "name" => "773-1.jpg"
                "alt" => null
                "width" => "1361"
                "height" => 833
                "path" => "/media/algebra_09/soltan-u19/1-1/773-1.webp?ts=1752831566"
              ]
              1 => array:5 [
                "name" => "773-2.jpg"
                "alt" => null
                "width" => "1418"
                "height" => 2414
                "path" => "/media/algebra_09/soltan-u19/1-1/773-2.webp?ts=1752831566"
              ]
              2 => array:5 [
                "name" => "773-3.jpg"
                "alt" => null
                "width" => "1358"
                "height" => 1447
                "path" => "/media/algebra_09/soltan-u19/1-1/773-3.webp?ts=1752831566"
              ]
            ]
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Element {#1173
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1554374
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1183
              #items: array:1 [
                0 => App\Models\Edition {#1174
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 5665
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 2 (rus)"
                    "field_order" => "3"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1177 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "2-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1179 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1180 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 5665
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 2 (rus)"
                    "field_order" => "3"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1177 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "2-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1179 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1180 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1108516"
              "type" => "task"
            ]
            "text" => "<p><strong>а)</strong> Для нахождения значения выражения $\cos 8\alpha - \cos 6\alpha - 2\cos 5\alpha \cdot \cos 3\alpha$ преобразуем его, используя тригонометрические формулы.<br>Применим формулу произведения косинусов для последнего слагаемого: $2\cos x \cos y = \cos(x+y) + \cos(x-y)$.<br>$2\cos 5\alpha \cdot \cos 3\alpha = \cos(5\alpha + 3\alpha) + \cos(5\alpha - 3\alpha) = \cos 8\alpha + \cos 2\alpha$.<br>Подставим полученное выражение в исходное:<br>$\cos 8\alpha - \cos 6\alpha - (\cos 8\alpha + \cos 2\alpha) = \cos 8\alpha - \cos 6\alpha - \cos 8\alpha - \cos 2\alpha = -(\cos 6\alpha + \cos 2\alpha)$.<br>Теперь необходимо найти значения $\cos 2\alpha$ и $\cos 6\alpha$, зная, что $\cos \alpha = -\frac{1}{\sqrt{3}}$.<br>Используем формулу косинуса двойного угла $\cos 2\alpha = 2\cos^2 \alpha - 1$:<br>$\cos 2\alpha = 2\left(-\frac{1}{\sqrt{3}}\right)^2 - 1 = 2 \cdot \frac{1}{3} - 1 = \frac{2}{3} - 1 = -\frac{1}{3}$.<br>Для вычисления $\cos 6\alpha$ применим формулу косинуса тройного угла к аргументу $2\alpha$: $\cos 3x = 4\cos^3 x - 3\cos x$.<br>$\cos 6\alpha = \cos(3 \cdot 2\alpha) = 4\cos^3(2\alpha) - 3\cos(2\alpha)$.<br>$\cos 6\alpha = 4\left(-\frac{1}{3}\right)^3 - 3\left(-\frac{1}{3}\right) = 4\left(-\frac{1}{27}\right) + 1 = -\frac{4}{27} + \frac{27}{27} = \frac{23}{27}$.<br>Теперь вычислим значение всего выражения:<br>$-(\cos 6\alpha + \cos 2\alpha) = -\left(\frac{23}{27} + \left(-\frac{1}{3}\right)\right) = -\left(\frac{23}{27} - \frac{9}{27}\right) = -\frac{14}{27}$.<br>Ответ: $-\frac{14}{27}$</p><p><strong>б)</strong> Для нахождения значения выражения $\sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha$ преобразуем его, используя формулу произведения синуса на косинус $\sin x \cos y = \frac{1}{2}(\sin(x+y) + \sin(x-y))$.<br>$\sin 2\alpha \cos 5\alpha = \frac{1}{2}(\sin(2\alpha+5\alpha) + \sin(2\alpha-5\alpha)) = \frac{1}{2}(\sin 7\alpha + \sin(-3\alpha)) = \frac{1}{2}(\sin 7\alpha - \sin 3\alpha)$.<br>$\sin \alpha \cos 6\alpha = \frac{1}{2}(\sin(\alpha+6\alpha) + \sin(\alpha-6\alpha)) = \frac{1}{2}(\sin 7\alpha + \sin(-5\alpha)) = \frac{1}{2}(\sin 7\alpha - \sin 5\alpha)$.<br>Подставим в исходное выражение:<br>$\frac{1}{2}(\sin 7\alpha - \sin 3\alpha) - \frac{1}{2}(\sin 7\alpha - \sin 5\alpha) = \frac{1}{2}\sin 7\alpha - \frac{1}{2}\sin 3\alpha - \frac{1}{2}\sin 7\alpha + \frac{1}{2}\sin 5\alpha = \frac{1}{2}(\sin 5\alpha - \sin 3\alpha)$.<br>Теперь применим формулу разности синусов $\sin x - \sin y = 2\cos\frac{x+y}{2}\sin\frac{x-y}{2}$:<br>$\frac{1}{2}(2\cos\frac{5\alpha+3\alpha}{2}\sin\frac{5\alpha-3\alpha}{2}) = \cos 4\alpha \sin \alpha$.<br>Нам дано, что $\sin \alpha = -\frac{1}{\sqrt{3}}$. Найдем $\cos 4\alpha$.<br>Сначала найдем $\cos 2\alpha$ по формуле $\cos 2\alpha = 1 - 2\sin^2 \alpha$:<br>$\cos 2\alpha = 1 - 2\left(-\frac{1}{\sqrt{3}}\right)^2 = 1 - 2 \cdot \frac{1}{3} = \frac{1}{3}$.<br>Теперь найдем $\cos 4\alpha$ по формуле $\cos 4\alpha = 2\cos^2(2\alpha) - 1$:<br>$\cos 4\alpha = 2\left(\frac{1}{3}\right)^2 - 1 = 2 \cdot \frac{1}{9} - 1 = \frac{2}{9} - 1 = -\frac{7}{9}$.<br>Вычислим итоговое значение:<br>$\cos 4\alpha \sin \alpha = \left(-\frac{7}{9}\right) \cdot \left(-\frac{1}{\sqrt{3}}\right) = \frac{7}{9\sqrt{3}} = \frac{7\sqrt{3}}{27}$.<br>Ответ: $\frac{7\sqrt{3}}{27}$</p><p><strong>в)</strong> Для нахождения значения выражения $\cos 7\alpha \cdot \cos 4\alpha - \cos 8\alpha \cdot \cos 3\alpha$ преобразуем его, используя формулу произведения косинусов $\cos x \cos y = \frac{1}{2}(\cos(x+y) + \cos(x-y))$.<br>$\cos 7\alpha \cos 4\alpha = \frac{1}{2}(\cos(7\alpha+4\alpha) + \cos(7\alpha-4\alpha)) = \frac{1}{2}(\cos 11\alpha + \cos 3\alpha)$.<br>$\cos 8\alpha \cos 3\alpha = \frac{1}{2}(\cos(8\alpha+3\alpha) + \cos(8\alpha-3\alpha)) = \frac{1}{2}(\cos 11\alpha + \cos 5\alpha)$.<br>Подставим в исходное выражение:<br>$\frac{1}{2}(\cos 11\alpha + \cos 3\alpha) - \frac{1}{2}(\cos 11\alpha + \cos 5\alpha) = \frac{1}{2}\cos 11\alpha + \frac{1}{2}\cos 3\alpha - \frac{1}{2}\cos 11\alpha - \frac{1}{2}\cos 5\alpha = \frac{1}{2}(\cos 3\alpha - \cos 5\alpha)$.<br>Применим формулу разности косинусов $\cos x - \cos y = -2\sin\frac{x+y}{2}\sin\frac{x-y}{2}$:<br>$\frac{1}{2}(-2\sin\frac{3\alpha+5\alpha}{2}\sin\frac{3\alpha-5\alpha}{2}) = -\sin(4\alpha)\sin(-\alpha) = \sin 4\alpha \sin \alpha$.<br>Выражение упростилось до $\sin 4\alpha \sin \alpha$. Нам дано $\cos \alpha = \frac{\sqrt{3}}{3}$.<br>Чтобы найти значение, выразим $\sin 4\alpha \sin \alpha$ через $\cos \alpha$.<br>$\sin 4\alpha = 2\sin 2\alpha \cos 2\alpha = 2(2\sin\alpha\cos\alpha)(2\cos^2\alpha-1)$.<br>Тогда все выражение равно $(\sin\alpha) \cdot (4\sin\alpha\cos\alpha(2\cos^2\alpha-1)) = 4\sin^2\alpha\cos\alpha(2\cos^2\alpha-1)$.<br>Найдем $\sin^2\alpha$ из основного тригонометрического тождества $\sin^2\alpha = 1 - \cos^2\alpha$:<br>$\sin^2\alpha = 1 - \left(\frac{\sqrt{3}}{3}\right)^2 = 1 - \frac{3}{9} = 1 - \frac{1}{3} = \frac{2}{3}$.<br>Подставим известные значения:<br>$4\left(\frac{2}{3}\right)\left(\frac{\sqrt{3}}{3}\right)\left(2\left(\frac{\sqrt{3}}{3}\right)^2-1\right) = \frac{8\sqrt{3}}{9}\left(2\cdot\frac{1}{3}-1\right) = \frac{8\sqrt{3}}{9}\left(\frac{2}{3}-1\right) = \frac{8\sqrt{3}}{9}\left(-\frac{1}{3}\right) = -\frac{8\sqrt{3}}{27}$.<br>Ответ: $-\frac{8\sqrt{3}}{27}$</p><p><strong>г)</strong> Исходное выражение $\sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha$ полностью совпадает с выражением из пункта б).<br>Как было показано в решении пункта б), данное выражение можно упростить до вида $\cos 4\alpha \sin \alpha$.<br>По условию $\sin \alpha = \frac{\sqrt{5}}{4}$. Нам осталось найти $\cos 4\alpha$.<br>Найдем $\cos 2\alpha$ по формуле $\cos 2\alpha = 1 - 2\sin^2 \alpha$:<br>$\cos 2\alpha = 1 - 2\left(\frac{\sqrt{5}}{4}\right)^2 = 1 - 2 \cdot \frac{5}{16} = 1 - \frac{10}{16} = 1 - \frac{5}{8} = \frac{3}{8}$.<br>Теперь найдем $\cos 4\alpha$ по формуле $\cos 4\alpha = 2\cos^2(2\alpha) - 1$:<br>$\cos 4\alpha = 2\left(\frac{3}{8}\right)^2 - 1 = 2 \cdot \frac{9}{64} - 1 = \frac{18}{64} - 1 = \frac{9}{32} - \frac{32}{32} = -\frac{23}{32}$.<br>Вычислим итоговое значение $\cos 4\alpha \sin \alpha$:<br>$\left(-\frac{23}{32}\right) \cdot \left(\frac{\sqrt{5}}{4}\right) = -\frac{23\sqrt{5}}{128}$.<br>Ответ: $-\frac{23\sqrt{5}}{128}$</p>"
          ]
          #original: array:6 [
            "id" => 1554374
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1183}
            "task" => array:2 [
              "refs" => "1108516"
              "type" => "task"
            ]
            "text" => "<p><strong>а)</strong> Для нахождения значения выражения $\cos 8\alpha - \cos 6\alpha - 2\cos 5\alpha \cdot \cos 3\alpha$ преобразуем его, используя тригонометрические формулы.<br>Применим формулу произведения косинусов для последнего слагаемого: $2\cos x \cos y = \cos(x+y) + \cos(x-y)$.<br>$2\cos 5\alpha \cdot \cos 3\alpha = \cos(5\alpha + 3\alpha) + \cos(5\alpha - 3\alpha) = \cos 8\alpha + \cos 2\alpha$.<br>Подставим полученное выражение в исходное:<br>$\cos 8\alpha - \cos 6\alpha - (\cos 8\alpha + \cos 2\alpha) = \cos 8\alpha - \cos 6\alpha - \cos 8\alpha - \cos 2\alpha = -(\cos 6\alpha + \cos 2\alpha)$.<br>Теперь необходимо найти значения $\cos 2\alpha$ и $\cos 6\alpha$, зная, что $\cos \alpha = -\frac{1}{\sqrt{3}}$.<br>Используем формулу косинуса двойного угла $\cos 2\alpha = 2\cos^2 \alpha - 1$:<br>$\cos 2\alpha = 2\left(-\frac{1}{\sqrt{3}}\right)^2 - 1 = 2 \cdot \frac{1}{3} - 1 = \frac{2}{3} - 1 = -\frac{1}{3}$.<br>Для вычисления $\cos 6\alpha$ применим формулу косинуса тройного угла к аргументу $2\alpha$: $\cos 3x = 4\cos^3 x - 3\cos x$.<br>$\cos 6\alpha = \cos(3 \cdot 2\alpha) = 4\cos^3(2\alpha) - 3\cos(2\alpha)$.<br>$\cos 6\alpha = 4\left(-\frac{1}{3}\right)^3 - 3\left(-\frac{1}{3}\right) = 4\left(-\frac{1}{27}\right) + 1 = -\frac{4}{27} + \frac{27}{27} = \frac{23}{27}$.<br>Теперь вычислим значение всего выражения:<br>$-(\cos 6\alpha + \cos 2\alpha) = -\left(\frac{23}{27} + \left(-\frac{1}{3}\right)\right) = -\left(\frac{23}{27} - \frac{9}{27}\right) = -\frac{14}{27}$.<br>Ответ: $-\frac{14}{27}$</p><p><strong>б)</strong> Для нахождения значения выражения $\sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha$ преобразуем его, используя формулу произведения синуса на косинус $\sin x \cos y = \frac{1}{2}(\sin(x+y) + \sin(x-y))$.<br>$\sin 2\alpha \cos 5\alpha = \frac{1}{2}(\sin(2\alpha+5\alpha) + \sin(2\alpha-5\alpha)) = \frac{1}{2}(\sin 7\alpha + \sin(-3\alpha)) = \frac{1}{2}(\sin 7\alpha - \sin 3\alpha)$.<br>$\sin \alpha \cos 6\alpha = \frac{1}{2}(\sin(\alpha+6\alpha) + \sin(\alpha-6\alpha)) = \frac{1}{2}(\sin 7\alpha + \sin(-5\alpha)) = \frac{1}{2}(\sin 7\alpha - \sin 5\alpha)$.<br>Подставим в исходное выражение:<br>$\frac{1}{2}(\sin 7\alpha - \sin 3\alpha) - \frac{1}{2}(\sin 7\alpha - \sin 5\alpha) = \frac{1}{2}\sin 7\alpha - \frac{1}{2}\sin 3\alpha - \frac{1}{2}\sin 7\alpha + \frac{1}{2}\sin 5\alpha = \frac{1}{2}(\sin 5\alpha - \sin 3\alpha)$.<br>Теперь применим формулу разности синусов $\sin x - \sin y = 2\cos\frac{x+y}{2}\sin\frac{x-y}{2}$:<br>$\frac{1}{2}(2\cos\frac{5\alpha+3\alpha}{2}\sin\frac{5\alpha-3\alpha}{2}) = \cos 4\alpha \sin \alpha$.<br>Нам дано, что $\sin \alpha = -\frac{1}{\sqrt{3}}$. Найдем $\cos 4\alpha$.<br>Сначала найдем $\cos 2\alpha$ по формуле $\cos 2\alpha = 1 - 2\sin^2 \alpha$:<br>$\cos 2\alpha = 1 - 2\left(-\frac{1}{\sqrt{3}}\right)^2 = 1 - 2 \cdot \frac{1}{3} = \frac{1}{3}$.<br>Теперь найдем $\cos 4\alpha$ по формуле $\cos 4\alpha = 2\cos^2(2\alpha) - 1$:<br>$\cos 4\alpha = 2\left(\frac{1}{3}\right)^2 - 1 = 2 \cdot \frac{1}{9} - 1 = \frac{2}{9} - 1 = -\frac{7}{9}$.<br>Вычислим итоговое значение:<br>$\cos 4\alpha \sin \alpha = \left(-\frac{7}{9}\right) \cdot \left(-\frac{1}{\sqrt{3}}\right) = \frac{7}{9\sqrt{3}} = \frac{7\sqrt{3}}{27}$.<br>Ответ: $\frac{7\sqrt{3}}{27}$</p><p><strong>в)</strong> Для нахождения значения выражения $\cos 7\alpha \cdot \cos 4\alpha - \cos 8\alpha \cdot \cos 3\alpha$ преобразуем его, используя формулу произведения косинусов $\cos x \cos y = \frac{1}{2}(\cos(x+y) + \cos(x-y))$.<br>$\cos 7\alpha \cos 4\alpha = \frac{1}{2}(\cos(7\alpha+4\alpha) + \cos(7\alpha-4\alpha)) = \frac{1}{2}(\cos 11\alpha + \cos 3\alpha)$.<br>$\cos 8\alpha \cos 3\alpha = \frac{1}{2}(\cos(8\alpha+3\alpha) + \cos(8\alpha-3\alpha)) = \frac{1}{2}(\cos 11\alpha + \cos 5\alpha)$.<br>Подставим в исходное выражение:<br>$\frac{1}{2}(\cos 11\alpha + \cos 3\alpha) - \frac{1}{2}(\cos 11\alpha + \cos 5\alpha) = \frac{1}{2}\cos 11\alpha + \frac{1}{2}\cos 3\alpha - \frac{1}{2}\cos 11\alpha - \frac{1}{2}\cos 5\alpha = \frac{1}{2}(\cos 3\alpha - \cos 5\alpha)$.<br>Применим формулу разности косинусов $\cos x - \cos y = -2\sin\frac{x+y}{2}\sin\frac{x-y}{2}$:<br>$\frac{1}{2}(-2\sin\frac{3\alpha+5\alpha}{2}\sin\frac{3\alpha-5\alpha}{2}) = -\sin(4\alpha)\sin(-\alpha) = \sin 4\alpha \sin \alpha$.<br>Выражение упростилось до $\sin 4\alpha \sin \alpha$. Нам дано $\cos \alpha = \frac{\sqrt{3}}{3}$.<br>Чтобы найти значение, выразим $\sin 4\alpha \sin \alpha$ через $\cos \alpha$.<br>$\sin 4\alpha = 2\sin 2\alpha \cos 2\alpha = 2(2\sin\alpha\cos\alpha)(2\cos^2\alpha-1)$.<br>Тогда все выражение равно $(\sin\alpha) \cdot (4\sin\alpha\cos\alpha(2\cos^2\alpha-1)) = 4\sin^2\alpha\cos\alpha(2\cos^2\alpha-1)$.<br>Найдем $\sin^2\alpha$ из основного тригонометрического тождества $\sin^2\alpha = 1 - \cos^2\alpha$:<br>$\sin^2\alpha = 1 - \left(\frac{\sqrt{3}}{3}\right)^2 = 1 - \frac{3}{9} = 1 - \frac{1}{3} = \frac{2}{3}$.<br>Подставим известные значения:<br>$4\left(\frac{2}{3}\right)\left(\frac{\sqrt{3}}{3}\right)\left(2\left(\frac{\sqrt{3}}{3}\right)^2-1\right) = \frac{8\sqrt{3}}{9}\left(2\cdot\frac{1}{3}-1\right) = \frac{8\sqrt{3}}{9}\left(\frac{2}{3}-1\right) = \frac{8\sqrt{3}}{9}\left(-\frac{1}{3}\right) = -\frac{8\sqrt{3}}{27}$.<br>Ответ: $-\frac{8\sqrt{3}}{27}$</p><p><strong>г)</strong> Исходное выражение $\sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha$ полностью совпадает с выражением из пункта б).<br>Как было показано в решении пункта б), данное выражение можно упростить до вида $\cos 4\alpha \sin \alpha$.<br>По условию $\sin \alpha = \frac{\sqrt{5}}{4}$. Нам осталось найти $\cos 4\alpha$.<br>Найдем $\cos 2\alpha$ по формуле $\cos 2\alpha = 1 - 2\sin^2 \alpha$:<br>$\cos 2\alpha = 1 - 2\left(\frac{\sqrt{5}}{4}\right)^2 = 1 - 2 \cdot \frac{5}{16} = 1 - \frac{10}{16} = 1 - \frac{5}{8} = \frac{3}{8}$.<br>Теперь найдем $\cos 4\alpha$ по формуле $\cos 4\alpha = 2\cos^2(2\alpha) - 1$:<br>$\cos 4\alpha = 2\left(\frac{3}{8}\right)^2 - 1 = 2 \cdot \frac{9}{64} - 1 = \frac{18}{64} - 1 = \frac{9}{32} - \frac{32}{32} = -\frac{23}{32}$.<br>Вычислим итоговое значение $\cos 4\alpha \sin \alpha$:<br>$\left(-\frac{23}{32}\right) \cdot \left(\frac{\sqrt{5}}{4}\right) = -\frac{23\sqrt{5}}{128}$.<br>Ответ: $-\frac{23\sqrt{5}}{128}$</p>"
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "next" => array:2 [
      "refs" => "1108517"
      "type" => "task"
    ]
    "previous" => array:2 [
      "refs" => "1108515"
      "type" => "task"
    ]
    "book" => Illuminate\Database\Eloquent\Collection {#1195
      #items: array:1 [
        0 => App\Models\Book {#1155
          #connection: "mysql"
          #table: "books"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:50 [
            "id" => 4298
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_tree_default_status" => "tasks"
            "field_pages_status" => null
            "field_subject" => Illuminate\Database\Eloquent\Collection {#1141
              #items: array:1 [
                0 => App\Models\Term {#1140
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:10 [
                    "id" => 6471
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Алгебра"
                    "field_abbreviated_name" => null
                    "field_cases" => array:6 [ …6]
                    "field_foreign_lang_name" => null
                    "field_short_name" => null
                    "field_subject_type" => "technical_subject"
                    "field_translit" => "algebra"
                  ]
                  #original: array:10 [
                    "id" => 6471
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Алгебра"
                    "field_abbreviated_name" => null
                    "field_cases" => array:6 [ …6]
                    "field_foreign_lang_name" => null
                    "field_short_name" => null
                    "field_subject_type" => "technical_subject"
                    "field_translit" => "algebra"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_class" => Illuminate\Database\Eloquent\Collection {#1139
              #items: array:1 [
                0 => App\Models\Term {#1146
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 5458
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "9"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "devjatyj"
                  ]
                  #original: array:6 [
                    "id" => 5458
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "9"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "devjatyj"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_publisher" => Illuminate\Database\Eloquent\Collection {#1145
              #items: array:1 [
                0 => App\Models\Term {#1144
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 7002
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Кокшетау"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "Kokshetau"
                  ]
                  #original: array:6 [
                    "id" => 7002
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Кокшетау"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "Kokshetau"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_author" => Illuminate\Database\Eloquent\Collection {#1142
              #items: array:3 [
                0 => App\Models\Term {#1143
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:12 [
                    "id" => 7003
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Солтан"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Генадий"
                    "field_patronymic" => "Николаевич"
                    "field_surname_rp" => null
                  ]
                  #original: array:12 [
                    "id" => 7003
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Солтан"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Генадий"
                    "field_patronymic" => "Николаевич"
                    "field_surname_rp" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
                1 => App\Models\Term {#1149
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:12 [
                    "id" => 7004
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Солтан"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Алла"
                    "field_patronymic" => "Евгеньевна"
                    "field_surname_rp" => null
                  ]
                  #original: array:12 [
                    "id" => 7004
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Солтан"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Алла"
                    "field_patronymic" => "Евгеньевна"
                    "field_surname_rp" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
                2 => App\Models\Term {#1147
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:12 [
                    "id" => 7005
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Жумадилова"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Аманбала"
                    "field_patronymic" => "Жумадиловна"
                    "field_surname_rp" => null
                  ]
                  #original: array:12 [
                    "id" => 7005
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Жумадилова"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Аманбала"
                    "field_patronymic" => "Жумадиловна"
                    "field_surname_rp" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1154
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_book_type" => Illuminate\Database\Eloquent\Collection {#1156
              #items: array:1 [
                0 => App\Models\Term {#1152
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:10 [
                    "id" => 6671
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Учебник"
                    "field_book_type_foreign" => null
                    "field_cases" => array:6 [ …6]
                    "field_plural_form" => null
                    "field_short_name" => null
                    "field_short_name_foreign" => null
                    "field_translit" => "uchebnik"
                  ]
                  #original: array:10 [
                    "id" => 6671
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Учебник"
                    "field_book_type_foreign" => null
                    "field_cases" => array:6 [ …6]
                    "field_plural_form" => null
                    "field_short_name" => null
                    "field_short_name_foreign" => null
                    "field_translit" => "uchebnik"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_country" => Illuminate\Database\Eloquent\Collection {#1150
              #items: array:1 [
                0 => App\Models\Term {#1153
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 6994
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Казахстан"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "kazakhstan"
                  ]
                  #original: array:6 [
                    "id" => 6994
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Казахстан"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "kazakhstan"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_city" => Illuminate\Database\Eloquent\Collection {#1151
              #items: array:1 [
                0 => App\Models\Term {#1181
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 6995
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Алматы"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "almaty"
                  ]
                  #original: array:6 [
                    "id" => 6995
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Алматы"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "almaty"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_series" => Illuminate\Database\Eloquent\Collection {#1182
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_umk" => Illuminate\Database\Eloquent\Collection {#1184
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1185
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1186
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_publication_number" => null
            "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1187
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1188
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_under_the_edition_degree" => null
            "field_cover_description" => null
            "field_publication_year" => "2019"
            "field_publication_year_until" => null
            "field_part" => ""
            "field_part_writing" => ""
            "field_second_foreign_language" => null
            "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
            "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
            "field_reserve_field" => null
            "field_link_to_source" => null
            "field_tasks_count" => "1291"
            "field_priority" => "4"
            "field_default_folder" => "/algebra_09/soltan-u19/"
            "field_isbn" => "978-601-317-424-2"
            "field_cover" => array:1 [
              0 => "/media/algebra_09/soltan-u19/covers/cover1.webp?ts=1752140452"
            ]
            "field_cover_alts" => array:1 [
              0 => ""
            ]
            "field_covers" => array:1 [
              0 => array:4 [
                "path" => "/media/algebra_09/soltan-u19/covers/cover1.webp?ts=1752140452"
                "alt" => ""
                "width" => "1940"
                "height" => "2895"
              ]
            ]
            "field_popular_book" => null
            "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1189
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_new_book" => Illuminate\Database\Eloquent\Collection {#1190
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_old_book" => Illuminate\Database\Eloquent\Collection {#1191
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
            "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1192
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "breadcrumbs" => array:3 [
              "class" => 380
              "subject" => 542
              "class_subject" => 386
            ]
          ]
          #original: array:50 [
            "id" => 4298
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_tree_default_status" => "tasks"
            "field_pages_status" => null
            "field_subject" => Illuminate\Database\Eloquent\Collection {#1141}
            "field_class" => Illuminate\Database\Eloquent\Collection {#1139}
            "field_publisher" => Illuminate\Database\Eloquent\Collection {#1145}
            "field_author" => Illuminate\Database\Eloquent\Collection {#1142}
            "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1154}
            "field_book_type" => Illuminate\Database\Eloquent\Collection {#1156}
            "field_country" => Illuminate\Database\Eloquent\Collection {#1150}
            "field_city" => Illuminate\Database\Eloquent\Collection {#1151}
            "field_series" => Illuminate\Database\Eloquent\Collection {#1182}
            "field_umk" => Illuminate\Database\Eloquent\Collection {#1184}
            "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1185}
            "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1186}
            "field_publication_number" => null
            "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1187}
            "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1188}
            "field_under_the_edition_degree" => null
            "field_cover_description" => null
            "field_publication_year" => "2019"
            "field_publication_year_until" => null
            "field_part" => ""
            "field_part_writing" => ""
            "field_second_foreign_language" => null
            "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
            "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
            "field_reserve_field" => null
            "field_link_to_source" => null
            "field_tasks_count" => "1291"
            "field_priority" => "4"
            "field_default_folder" => "/algebra_09/soltan-u19/"
            "field_isbn" => "978-601-317-424-2"
            "field_cover" => array:1 [
              0 => "/media/algebra_09/soltan-u19/covers/cover1.webp?ts=1752140452"
            ]
            "field_cover_alts" => array:1 [
              0 => ""
            ]
            "field_covers" => array:1 [
              0 => array:4 [
                "path" => "/media/algebra_09/soltan-u19/covers/cover1.webp?ts=1752140452"
                "alt" => ""
                "width" => "1940"
                "height" => "2895"
              ]
            ]
            "field_popular_book" => null
            "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1189}
            "field_new_book" => Illuminate\Database\Eloquent\Collection {#1190}
            "field_old_book" => Illuminate\Database\Eloquent\Collection {#1191}
            "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
            "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1192}
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "breadcrumbs" => array:3 [
              "class" => 380
              "subject" => 542
              "class_subject" => 386
            ]
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "page" => Illuminate\Database\Eloquent\Collection {#1357
      #items: array:1 [
        0 => App\Models\BookPage {#1032
          #connection: "mysql"
          #table: "book_pages"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:21 [
            "id" => 1097960
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_page_start" => "218"
            "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/page-218"
            "field_display_title" => "218"
            "field_folder" => "folder1"
            "field_image_name" => "218"
            "field_branch_parent" => Illuminate\Database\Eloquent\Collection {#1023
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_weight" => "0"
            "field_book_parent" => Illuminate\Database\Eloquent\Collection {#1026
              #items: array:1 [
                0 => App\Models\Book {#1193
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1194 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1197 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1199 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1201 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1205 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1206 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1208 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1210 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1212 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1213 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1214 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1215 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1216 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1217 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1218 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1219 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1220 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1221 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #original: array:50 [
                    "id" => 4298
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1194 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1197 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1199 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1201 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1205 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1206 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1208 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1210 …2}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1212 …2}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1213 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1214 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1215 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1216 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1217 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся 9 класса общеобразовательных школ"
                    "field_allowed" => "Рекомендовано Министерством образования и науки Республики Казахстан"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => "4"
                    "field_default_folder" => "/algebra_09/soltan-u19/"
                    "field_isbn" => "978-601-317-424-2"
                    "field_cover" => array:1 [ …1]
                    "field_cover_alts" => array:1 [ …1]
                    "field_covers" => array:1 [ …1]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1218 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1219 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1220 …2}
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1221 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "edition_groups" => Illuminate\Database\Eloquent\Collection {#1222
              #items: []
              #escapeWhenCastingToString: false
            }
            "content" => Illuminate\Database\Eloquent\Collection {#1223
              #items: array:1 [
                0 => App\Models\Element {#1224
                  #connection: "mysql"
                  #table: "elements"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 1261111
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "edition" => Illuminate\Database\Eloquent\Collection {#1225 …2}
                    "book_page" => array:2 [ …2]
                    "img" => array:1 [ …1]
                  ]
                  #original: array:6 [
                    "id" => 1261111
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "edition" => Illuminate\Database\Eloquent\Collection {#1225 …2}
                    "book_page" => array:2 [ …2]
                    "img" => array:1 [ …1]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "next" => array:2 [
              "refs" => "1097961"
              "type" => "book_page"
            ]
            "previous" => array:2 [
              "refs" => "1097959"
              "type" => "book_page"
            ]
            "tasks" => Illuminate\Database\Eloquent\Collection {#1232
              #items: array:7 [
                0 => App\Models\Task {#1233
                  #connection: "mysql"
                  #table: "tasks"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1108511
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "217"
                    "field_page_end" => "218"
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-768"
                    "field_display_title" => "768"
                    "field_outside_task" => "0"
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1234 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_match" => null
                    "breadcrumbs" => []
                    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1236 …2}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1237 …2}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1242 …2}
                    "content" => Illuminate\Database\Eloquent\Collection {#1251 …2}
                    "next" => array:2 [ …2]
                    "previous" => array:2 [ …2]
                    "book" => Illuminate\Database\Eloquent\Collection {#1276 …2}
                    "page" => array:2 [ …2]
                  ]
                  #original: array:24 [
                    "id" => 1108511
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "217"
                    "field_page_end" => "218"
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-768"
                    "field_display_title" => "768"
                    "field_outside_task" => "0"
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1234 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_match" => null
                    "breadcrumbs" => []
                    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1236 …2}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1237 …2}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1242 …2}
                    "content" => Illuminate\Database\Eloquent\Collection {#1251 …2}
                    "next" => array:2 [ …2]
                    "previous" => array:2 [ …2]
                    "book" => Illuminate\Database\Eloquent\Collection {#1276 …2}
                    "page" => array:2 [ …2]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
                1 => App\Models\Task {#1277
                  #connection: "mysql"
                  #table: "tasks"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1108512
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "218"
                    "field_page_end" => null
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-769"
                    "field_display_title" => "769"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1278 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_match" => null
                    "breadcrumbs" => []
                    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1279 …2}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1280 …2}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1281 …2}
                    "content" => Illuminate\Database\Eloquent\Collection {#1282 …2}
                    "next" => array:2 [ …2]
                    "previous" => array:2 [ …2]
                    "book" => Illuminate\Database\Eloquent\Collection {#1289 …2}
                    "page" => array:2 [ …2]
                  ]
                  #original: array:24 [
                    "id" => 1108512
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "218"
                    "field_page_end" => null
                    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-769"
                    "field_display_title" => "769"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1278 …2}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_match" => null
                    "breadcrumbs" => []
                    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1279 …2}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1280 …2}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1281 …2}
                    "content" => Illuminate\Database\Eloquent\Collection {#1282 …2}
                    "next" => array:2 [ …2]
                     …3
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
                2 => App\Models\Task {#1290
                  #connection: "mysql"
                  #table: "tasks"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [ …24]
                  #original: array:24 [ …24]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
                3 => App\Models\Task {#1303
                  #connection: "mysql"
                  #table: "tasks"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [ …24]
                  #original: array:24 [ …24]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
                4 => App\Models\Task {#1316
                  #connection: "mysql"
                  #table: "tasks"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [ …24]
                  #original: array:24 [ …24]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
                5 => App\Models\Task {#1329
                  #connection: "mysql"
                  #table: "tasks"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [ …24]
                  #original: array:24 [ …24]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
                6 => App\Models\Task {#1342
                  #connection: "mysql"
                  #table: "tasks"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [ …24]
                  #original: array:24 [ …24]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:21 [
            "id" => 1097960
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_page_start" => "218"
            "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/page-218"
            "field_display_title" => "218"
            "field_folder" => "folder1"
            "field_image_name" => "218"
            "field_branch_parent" => Illuminate\Database\Eloquent\Collection {#1023}
            "field_weight" => "0"
            "field_book_parent" => Illuminate\Database\Eloquent\Collection {#1026}
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "edition_groups" => Illuminate\Database\Eloquent\Collection {#1222}
            "content" => Illuminate\Database\Eloquent\Collection {#1223}
            "next" => array:2 [
              "refs" => "1097961"
              "type" => "book_page"
            ]
            "previous" => array:2 [
              "refs" => "1097959"
              "type" => "book_page"
            ]
            "tasks" => Illuminate\Database\Eloquent\Collection {#1232}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
  ]
  #original: array:24 [
    "id" => 1108516
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "218"
    "field_page_end" => null
    "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-773"
    "field_display_title" => "773"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037}
    "field_metatags_title" => null
    "field_metatags_description" => null
    "field_h1" => null
    "field_description_top" => null
    "field_description_bottom" => null
    "field_match" => null
    "breadcrumbs" => []
    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1035}
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1071}
    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1138}
    "content" => Illuminate\Database\Eloquent\Collection {#1148}
    "next" => array:2 [
      "refs" => "1108517"
      "type" => "task"
    ]
    "previous" => array:2 [
      "refs" => "1108515"
      "type" => "task"
    ]
    "book" => Illuminate\Database\Eloquent\Collection {#1195}
    "page" => array:2 [
      "refs" => "1097960"
      "type" => "book_page"
    ]
  ]
  #changes: []
  #casts: []
  #classCastCache: []
  #attributeCastCache: []
  #dateFormat: null
  #appends: []
  #dispatchesEvents: []
  #observables: []
  #relations: []
  #touches: []
  +timestamps: true
  +usesUniqueIds: false
  #hidden: []
  #visible: []
  #fillable: []
  #guarded: array:1 [
    0 => "*"
  ]
}
№773 (с. 218)
Условие. №773 (с. 218)
скриншот условия
Алгебра, 9 класс Учебник, авторы: Солтан Генадий Николаевич, Солтан Алла Евгеньевна, Жумадилова Аманбала Жумадиловна, издательство Кокшетау, Алматы, 2019, страница 218, номер 773, Условие

773. Найдите значение выражения:

a) $ \cos 8\alpha - \cos 6\alpha - 2\cos 5\alpha \cdot \cos 3\alpha, \text{ если } \cos \alpha = -\frac{1}{\sqrt{3}}; $

б) $ \sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha, \text{ если } \sin \alpha = -\frac{1}{\sqrt{3}}; $

в) $ \cos 7\alpha \cdot \cos 4\alpha - \cos 8\alpha \cdot \cos 3\alpha, \text{ если } \cos \alpha = \frac{\sqrt{3}}{3}; $

г) $ \sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha, \text{ если } \sin \alpha = \frac{\sqrt{5}}{4}. $

Решение. №773 (с. 218)
Алгебра, 9 класс Учебник, авторы: Солтан Генадий Николаевич, Солтан Алла Евгеньевна, Жумадилова Аманбала Жумадиловна, издательство Кокшетау, Алматы, 2019, страница 218, номер 773, Решение
Алгебра, 9 класс Учебник, авторы: Солтан Генадий Николаевич, Солтан Алла Евгеньевна, Жумадилова Аманбала Жумадиловна, издательство Кокшетау, Алматы, 2019, страница 218, номер 773, Решение (продолжение 2)
Решение 2 (rus). №773 (с. 218)

а) Для нахождения значения выражения $\cos 8\alpha - \cos 6\alpha - 2\cos 5\alpha \cdot \cos 3\alpha$ преобразуем его, используя тригонометрические формулы.
Применим формулу произведения косинусов для последнего слагаемого: $2\cos x \cos y = \cos(x+y) + \cos(x-y)$.
$2\cos 5\alpha \cdot \cos 3\alpha = \cos(5\alpha + 3\alpha) + \cos(5\alpha - 3\alpha) = \cos 8\alpha + \cos 2\alpha$.
Подставим полученное выражение в исходное:
$\cos 8\alpha - \cos 6\alpha - (\cos 8\alpha + \cos 2\alpha) = \cos 8\alpha - \cos 6\alpha - \cos 8\alpha - \cos 2\alpha = -(\cos 6\alpha + \cos 2\alpha)$.
Теперь необходимо найти значения $\cos 2\alpha$ и $\cos 6\alpha$, зная, что $\cos \alpha = -\frac{1}{\sqrt{3}}$.
Используем формулу косинуса двойного угла $\cos 2\alpha = 2\cos^2 \alpha - 1$:
$\cos 2\alpha = 2\left(-\frac{1}{\sqrt{3}}\right)^2 - 1 = 2 \cdot \frac{1}{3} - 1 = \frac{2}{3} - 1 = -\frac{1}{3}$.
Для вычисления $\cos 6\alpha$ применим формулу косинуса тройного угла к аргументу $2\alpha$: $\cos 3x = 4\cos^3 x - 3\cos x$.
$\cos 6\alpha = \cos(3 \cdot 2\alpha) = 4\cos^3(2\alpha) - 3\cos(2\alpha)$.
$\cos 6\alpha = 4\left(-\frac{1}{3}\right)^3 - 3\left(-\frac{1}{3}\right) = 4\left(-\frac{1}{27}\right) + 1 = -\frac{4}{27} + \frac{27}{27} = \frac{23}{27}$.
Теперь вычислим значение всего выражения:
$-(\cos 6\alpha + \cos 2\alpha) = -\left(\frac{23}{27} + \left(-\frac{1}{3}\right)\right) = -\left(\frac{23}{27} - \frac{9}{27}\right) = -\frac{14}{27}$.
Ответ: $-\frac{14}{27}$

б) Для нахождения значения выражения $\sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha$ преобразуем его, используя формулу произведения синуса на косинус $\sin x \cos y = \frac{1}{2}(\sin(x+y) + \sin(x-y))$.
$\sin 2\alpha \cos 5\alpha = \frac{1}{2}(\sin(2\alpha+5\alpha) + \sin(2\alpha-5\alpha)) = \frac{1}{2}(\sin 7\alpha + \sin(-3\alpha)) = \frac{1}{2}(\sin 7\alpha - \sin 3\alpha)$.
$\sin \alpha \cos 6\alpha = \frac{1}{2}(\sin(\alpha+6\alpha) + \sin(\alpha-6\alpha)) = \frac{1}{2}(\sin 7\alpha + \sin(-5\alpha)) = \frac{1}{2}(\sin 7\alpha - \sin 5\alpha)$.
Подставим в исходное выражение:
$\frac{1}{2}(\sin 7\alpha - \sin 3\alpha) - \frac{1}{2}(\sin 7\alpha - \sin 5\alpha) = \frac{1}{2}\sin 7\alpha - \frac{1}{2}\sin 3\alpha - \frac{1}{2}\sin 7\alpha + \frac{1}{2}\sin 5\alpha = \frac{1}{2}(\sin 5\alpha - \sin 3\alpha)$.
Теперь применим формулу разности синусов $\sin x - \sin y = 2\cos\frac{x+y}{2}\sin\frac{x-y}{2}$:
$\frac{1}{2}(2\cos\frac{5\alpha+3\alpha}{2}\sin\frac{5\alpha-3\alpha}{2}) = \cos 4\alpha \sin \alpha$.
Нам дано, что $\sin \alpha = -\frac{1}{\sqrt{3}}$. Найдем $\cos 4\alpha$.
Сначала найдем $\cos 2\alpha$ по формуле $\cos 2\alpha = 1 - 2\sin^2 \alpha$:
$\cos 2\alpha = 1 - 2\left(-\frac{1}{\sqrt{3}}\right)^2 = 1 - 2 \cdot \frac{1}{3} = \frac{1}{3}$.
Теперь найдем $\cos 4\alpha$ по формуле $\cos 4\alpha = 2\cos^2(2\alpha) - 1$:
$\cos 4\alpha = 2\left(\frac{1}{3}\right)^2 - 1 = 2 \cdot \frac{1}{9} - 1 = \frac{2}{9} - 1 = -\frac{7}{9}$.
Вычислим итоговое значение:
$\cos 4\alpha \sin \alpha = \left(-\frac{7}{9}\right) \cdot \left(-\frac{1}{\sqrt{3}}\right) = \frac{7}{9\sqrt{3}} = \frac{7\sqrt{3}}{27}$.
Ответ: $\frac{7\sqrt{3}}{27}$

в) Для нахождения значения выражения $\cos 7\alpha \cdot \cos 4\alpha - \cos 8\alpha \cdot \cos 3\alpha$ преобразуем его, используя формулу произведения косинусов $\cos x \cos y = \frac{1}{2}(\cos(x+y) + \cos(x-y))$.
$\cos 7\alpha \cos 4\alpha = \frac{1}{2}(\cos(7\alpha+4\alpha) + \cos(7\alpha-4\alpha)) = \frac{1}{2}(\cos 11\alpha + \cos 3\alpha)$.
$\cos 8\alpha \cos 3\alpha = \frac{1}{2}(\cos(8\alpha+3\alpha) + \cos(8\alpha-3\alpha)) = \frac{1}{2}(\cos 11\alpha + \cos 5\alpha)$.
Подставим в исходное выражение:
$\frac{1}{2}(\cos 11\alpha + \cos 3\alpha) - \frac{1}{2}(\cos 11\alpha + \cos 5\alpha) = \frac{1}{2}\cos 11\alpha + \frac{1}{2}\cos 3\alpha - \frac{1}{2}\cos 11\alpha - \frac{1}{2}\cos 5\alpha = \frac{1}{2}(\cos 3\alpha - \cos 5\alpha)$.
Применим формулу разности косинусов $\cos x - \cos y = -2\sin\frac{x+y}{2}\sin\frac{x-y}{2}$:
$\frac{1}{2}(-2\sin\frac{3\alpha+5\alpha}{2}\sin\frac{3\alpha-5\alpha}{2}) = -\sin(4\alpha)\sin(-\alpha) = \sin 4\alpha \sin \alpha$.
Выражение упростилось до $\sin 4\alpha \sin \alpha$. Нам дано $\cos \alpha = \frac{\sqrt{3}}{3}$.
Чтобы найти значение, выразим $\sin 4\alpha \sin \alpha$ через $\cos \alpha$.
$\sin 4\alpha = 2\sin 2\alpha \cos 2\alpha = 2(2\sin\alpha\cos\alpha)(2\cos^2\alpha-1)$.
Тогда все выражение равно $(\sin\alpha) \cdot (4\sin\alpha\cos\alpha(2\cos^2\alpha-1)) = 4\sin^2\alpha\cos\alpha(2\cos^2\alpha-1)$.
Найдем $\sin^2\alpha$ из основного тригонометрического тождества $\sin^2\alpha = 1 - \cos^2\alpha$:
$\sin^2\alpha = 1 - \left(\frac{\sqrt{3}}{3}\right)^2 = 1 - \frac{3}{9} = 1 - \frac{1}{3} = \frac{2}{3}$.
Подставим известные значения:
$4\left(\frac{2}{3}\right)\left(\frac{\sqrt{3}}{3}\right)\left(2\left(\frac{\sqrt{3}}{3}\right)^2-1\right) = \frac{8\sqrt{3}}{9}\left(2\cdot\frac{1}{3}-1\right) = \frac{8\sqrt{3}}{9}\left(\frac{2}{3}-1\right) = \frac{8\sqrt{3}}{9}\left(-\frac{1}{3}\right) = -\frac{8\sqrt{3}}{27}$.
Ответ: $-\frac{8\sqrt{3}}{27}$

г) Исходное выражение $\sin 2\alpha \cdot \cos 5\alpha - \sin \alpha \cdot \cos 6\alpha$ полностью совпадает с выражением из пункта б).
Как было показано в решении пункта б), данное выражение можно упростить до вида $\cos 4\alpha \sin \alpha$.
По условию $\sin \alpha = \frac{\sqrt{5}}{4}$. Нам осталось найти $\cos 4\alpha$.
Найдем $\cos 2\alpha$ по формуле $\cos 2\alpha = 1 - 2\sin^2 \alpha$:
$\cos 2\alpha = 1 - 2\left(\frac{\sqrt{5}}{4}\right)^2 = 1 - 2 \cdot \frac{5}{16} = 1 - \frac{10}{16} = 1 - \frac{5}{8} = \frac{3}{8}$.
Теперь найдем $\cos 4\alpha$ по формуле $\cos 4\alpha = 2\cos^2(2\alpha) - 1$:
$\cos 4\alpha = 2\left(\frac{3}{8}\right)^2 - 1 = 2 \cdot \frac{9}{64} - 1 = \frac{18}{64} - 1 = \frac{9}{32} - \frac{32}{32} = -\frac{23}{32}$.
Вычислим итоговое значение $\cos 4\alpha \sin \alpha$:
$\left(-\frac{23}{32}\right) \cdot \left(\frac{\sqrt{5}}{4}\right) = -\frac{23\sqrt{5}}{128}$.
Ответ: $-\frac{23\sqrt{5}}{128}$

Помогло решение? Оставьте отзыв в комментариях ниже.

Присоединяйтесь к Телеграм-группе @top_gdz

Присоединиться

Мы подготовили для вас ответ c подробным объяснением домашего задания по алгебре за 9 класс, для упражнения номер 773 расположенного на странице 218 к учебнику 2019 года издания для учащихся школ и гимназий.

Теперь на нашем сайте ГДЗ.ТОП вы всегда легко и бесплатно найдёте условие с правильным ответом на вопрос «Как решить ДЗ» и «Как сделать» задание по алгебре к упражнению №773 (с. 218), авторов: Солтан (Генадий Николаевич), Солтан (Алла Евгеньевна), Жумадилова (Аманбала Жумадиловна), учебного пособия издательства Кокшетау.