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Номер 729, страница 208 - гдз по алгебре 9 класс учебник Солтан, Солтан
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
Популярные ГДЗ в 9 классе
IV. Тригонометрия. 27. Формулы тригонометрических функций двойного и половинного углов - номер 729, страница 208.
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" => 1108470 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-729" "field_display_title" => "729" "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 #items: array:1 [ …1] #escapeWhenCastingToString: false } "field_class" => Illuminate\Database\Eloquent\Collection {#1043 #items: array:1 [ …1] #escapeWhenCastingToString: false } "field_publisher" => Illuminate\Database\Eloquent\Collection {#1045 #items: array:1 [ …1] #escapeWhenCastingToString: false } "field_author" => Illuminate\Database\Eloquent\Collection {#1047 #items: array:3 [ …3] #escapeWhenCastingToString: false } "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1051 #items: [] #escapeWhenCastingToString: false } "field_book_type" => Illuminate\Database\Eloquent\Collection {#1052 #items: array:1 [ …1] #escapeWhenCastingToString: false } "field_country" => Illuminate\Database\Eloquent\Collection {#1054 #items: array:1 [ …1] #escapeWhenCastingToString: false } "field_city" => Illuminate\Database\Eloquent\Collection {#1056 #items: array:1 [ …1] #escapeWhenCastingToString: false } "field_series" => Illuminate\Database\Eloquent\Collection {#1058 #items: [] #escapeWhenCastingToString: false } "field_umk" => Illuminate\Database\Eloquent\Collection {#1059 #items: [] #escapeWhenCastingToString: false } "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1060 #items: [] #escapeWhenCastingToString: false } "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1061 #items: [] #escapeWhenCastingToString: false } "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1062 #items: [] #escapeWhenCastingToString: false } "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1063 #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 [ …4] ] "field_popular_book" => null "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1064 #items: [] #escapeWhenCastingToString: false } "field_new_book" => Illuminate\Database\Eloquent\Collection {#1065 #items: [] #escapeWhenCastingToString: false } "field_old_book" => Illuminate\Database\Eloquent\Collection {#1066 #items: [] #escapeWhenCastingToString: false } "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1067 #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 {#1041} "field_class" => Illuminate\Database\Eloquent\Collection {#1043} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1045} "field_author" => Illuminate\Database\Eloquent\Collection {#1047} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1051} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1052} "field_country" => Illuminate\Database\Eloquent\Collection {#1054} "field_city" => Illuminate\Database\Eloquent\Collection {#1056} "field_series" => Illuminate\Database\Eloquent\Collection {#1058} "field_umk" => Illuminate\Database\Eloquent\Collection {#1059} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1060} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1061} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1062} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1063} "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 [ …4] ] "field_popular_book" => null "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1064} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1065} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1066} "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1067} "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 } "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 {#1104 #items: array:2 [ 0 => App\Models\Branch {#1112 #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 {#1113 #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 {#1144 #items: array:1 [ 0 => App\Models\Book {#1114 #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 {#1116 #items: array:1 [ 0 => App\Models\Term {#1115 #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 [ "field_accusative_case" => "алгебру" "field_creative_case" => "алгеброй" "field_dative_case" => "алгебре" "field_genitive_case" => "алгебры" "field_nominative_case" => "алгебра" "field_prepositional_case" => "алгебре" ] "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 [ "field_accusative_case" => "алгебру" "field_creative_case" => "алгеброй" "field_dative_case" => "алгебре" "field_genitive_case" => "алгебры" "field_nominative_case" => "алгебра" "field_prepositional_case" => "алгебре" ] "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 {#1117 #items: array:1 [ 0 => App\Models\Term {#1118 #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 [ "field_accusative_case" => "девятый" "field_creative_case" => "девятым" "field_dative_case" => "девятому" "field_genitive_case" => "девятого" "field_nominative_case" => "девятый" "field_prepositional_case" => "девятом" ] "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 [ "field_accusative_case" => "девятый" "field_creative_case" => "девятым" "field_dative_case" => "девятому" "field_genitive_case" => "девятого" "field_nominative_case" => "девятый" "field_prepositional_case" => "девятом" ] "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 {#1119 #items: array:1 [ 0 => App\Models\Term {#1120 #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 [ "field_accusative_case" => null "field_creative_case" => null "field_dative_case" => null "field_genitive_case" => null "field_nominative_case" => null "field_prepositional_case" => null ] "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 [ "field_accusative_case" => null "field_creative_case" => null …4 ] "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 {#1121 #items: array:3 [ 0 => App\Models\Term {#1122 #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 {#1123 #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 {#1124 #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 {#1125 #items: [] #escapeWhenCastingToString: false } "field_book_type" => Illuminate\Database\Eloquent\Collection {#1126 #items: array:1 [ 0 => App\Models\Term {#1127 #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 {#1128 #items: array:1 [ 0 => App\Models\Term {#1129 #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 {#1130 #items: array:1 [ 0 => App\Models\Term {#1131 #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 {#1132 #items: [] #escapeWhenCastingToString: false } "field_umk" => Illuminate\Database\Eloquent\Collection {#1133 #items: [] #escapeWhenCastingToString: false } "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1134 #items: [] #escapeWhenCastingToString: false } "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1135 #items: [] #escapeWhenCastingToString: false } "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1136 #items: [] #escapeWhenCastingToString: false } "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1137 #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 {#1138 #items: [] #escapeWhenCastingToString: false } "field_new_book" => Illuminate\Database\Eloquent\Collection {#1139 #items: [] #escapeWhenCastingToString: false } "field_old_book" => Illuminate\Database\Eloquent\Collection {#1140 #items: [] #escapeWhenCastingToString: false } "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1141 #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 {#1116} "field_class" => Illuminate\Database\Eloquent\Collection {#1117} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1119} "field_author" => Illuminate\Database\Eloquent\Collection {#1121} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1125} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1126} "field_country" => Illuminate\Database\Eloquent\Collection {#1128} "field_city" => Illuminate\Database\Eloquent\Collection {#1130} "field_series" => Illuminate\Database\Eloquent\Collection {#1132} "field_umk" => Illuminate\Database\Eloquent\Collection {#1133} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1134} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1135} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1136} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1137} "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 {#1138} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1139} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1140} "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1141} "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 } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1142 #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 {#1113} "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 {#1144} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1142} ] #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 {#1143 #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" => 1107669 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "27. Формулы тригонометрических функций двойного и половинного углов" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1145 #items: [] #escapeWhenCastingToString: false } "field_page_start" => "203" "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 {#1146 #items: array:1 [ 0 => App\Models\Book {#1114} ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1147 #items: array:1 [ 0 => App\Models\Branch {#1034} ] #escapeWhenCastingToString: false } ] #original: array:24 [ "id" => 1107669 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "27. Формулы тригонометрических функций двойного и половинного углов" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1145} "field_page_start" => "203" "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 {#1146} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1147} ] #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 {#1096 #items: array:3 [ 0 => App\Models\Element {#1085 #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" => 1277084 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1076 #items: array:1 [ 0 => App\Models\Edition {#1086 #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 {#1080 #items: array:1 [ …1] #escapeWhenCastingToString: false } "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 {#1083 #items: [] #escapeWhenCastingToString: false } "field_comment" => null "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1082 #items: [] #escapeWhenCastingToString: false } "field_process_formula" => "katex" "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1081 #items: [] #escapeWhenCastingToString: false } "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 {#1080} "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 {#1083} "field_comment" => null "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1082} "field_process_formula" => "katex" "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1081} "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" => "1108470" "type" => "task" ] "text" => "<p><strong>729.</strong> Упростите выражение:</p><p><strong>a)</strong> $16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha$;</p><p><strong>б)</strong> $(\cos^3\alpha + \sin^3\alpha)(\cos \alpha - \sin \alpha)$;</p><p><strong>в)</strong> $\sin^4\alpha + \cos^4\alpha - \frac{1}{4} \cos 4\alpha$;</p><p><strong>г)</strong> $\cos^4\alpha - 6\cos^2\alpha \sin^2\alpha + \sin^4\alpha$.</p>" "img" => array:1 [ 0 => array:5 [ "name" => "729-1.jpg" "alt" => null "width" => "1543" "height" => 313 "path" => "/media/algebra_09/soltan-u19/0-1/729-1.webp?ts=1752834734" ] ] ] #original: array:7 [ "id" => 1277084 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1076} "task" => array:2 [ "refs" => "1108470" "type" => "task" ] "text" => "<p><strong>729.</strong> Упростите выражение:</p><p><strong>a)</strong> $16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha$;</p><p><strong>б)</strong> $(\cos^3\alpha + \sin^3\alpha)(\cos \alpha - \sin \alpha)$;</p><p><strong>в)</strong> $\sin^4\alpha + \cos^4\alpha - \frac{1}{4} \cos 4\alpha$;</p><p><strong>г)</strong> $\cos^4\alpha - 6\cos^2\alpha \sin^2\alpha + \sin^4\alpha$.</p>" "img" => array:1 [ 0 => array:5 [ "name" => "729-1.jpg" "alt" => null "width" => "1543" "height" => 313 "path" => "/media/algebra_09/soltan-u19/0-1/729-1.webp?ts=1752834734" ] ] ] #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 {#1078 #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" => 1278375 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1107 #items: array:1 [ 0 => App\Models\Edition {#1079 #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 {#1074 #items: array:1 [ …1] #escapeWhenCastingToString: false } "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 {#1075 #items: [] #escapeWhenCastingToString: false } "field_comment" => null "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1072 #items: [] #escapeWhenCastingToString: false } "field_process_formula" => "" "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1103 #items: [] #escapeWhenCastingToString: false } "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 {#1074} "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 {#1075} "field_comment" => null "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1072} "field_process_formula" => "" "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1103} "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" => "1108470" "type" => "task" ] "img" => array:2 [ 0 => array:5 [ "name" => "729-1.jpg" "alt" => null "width" => "1379" "height" => 1108 "path" => "/media/algebra_09/soltan-u19/1-1/729-1.webp?ts=1752831534" ] 1 => array:5 [ "name" => "729-2.jpg" "alt" => null "width" => "1421" "height" => 1401 "path" => "/media/algebra_09/soltan-u19/1-1/729-2.webp?ts=1752831534" ] ] ] #original: array:6 [ "id" => 1278375 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1107} "task" => array:2 [ "refs" => "1108470" "type" => "task" ] "img" => array:2 [ 0 => array:5 [ "name" => "729-1.jpg" "alt" => null "width" => "1379" "height" => 1108 "path" => "/media/algebra_09/soltan-u19/1-1/729-1.webp?ts=1752831534" ] 1 => array:5 [ "name" => "729-2.jpg" "alt" => null "width" => "1421" "height" => 1401 "path" => "/media/algebra_09/soltan-u19/1-1/729-2.webp?ts=1752831534" ] ] ] #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 {#1102 #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" => 1554330 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1152 #items: array:1 [ 0 => App\Models\Edition {#1111 #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 {#1108 #items: array:1 [ …1] #escapeWhenCastingToString: false } "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 {#1106 #items: [] #escapeWhenCastingToString: false } "field_comment" => null "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1148 #items: [] #escapeWhenCastingToString: false } "field_process_formula" => "katex" "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1149 #items: [] #escapeWhenCastingToString: false } "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 {#1108} "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 {#1106} "field_comment" => null "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1148} "field_process_formula" => "katex" "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1149} "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" => "1108470" "type" => "task" ] "text" => "<p><strong>а)</strong> Для упрощения выражения $16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha$ будем последовательно применять формулу синуса двойного угла $ \sin(2x) = 2\sin x \cos x $.<br>Сначала сгруппируем множители $\cos \alpha$ и $\sin \alpha$:<br>$16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha = 8\cos 4\alpha \cos 2\alpha (2\sin \alpha \cos \alpha)$<br>Применяя формулу, получаем $\sin 2\alpha$:<br>$= 8\cos 4\alpha \cos 2\alpha \sin 2\alpha$<br>Теперь сгруппируем $\cos 2\alpha$ и $\sin 2\alpha$:<br>$= 4\cos 4\alpha (2\sin 2\alpha \cos 2\alpha)$<br>Применяя формулу, получаем $\sin 4\alpha$:<br>$= 4\cos 4\alpha \sin 4\alpha$<br>И еще раз применяем ту же формулу:<br>$= 2(2\sin 4\alpha \cos 4\alpha) = 2\sin(2 \cdot 4\alpha) = 2\sin 8\alpha$<br>Ответ: $2\sin 8\alpha$</p><p><strong>б)</strong> В выражении $(\cos^3\alpha + \sin^3\alpha)(\cos \alpha - \sin \alpha)$ раскроем первую скобку, используя формулу суммы кубов $a^3+b^3=(a+b)(a^2-ab+b^2)$ и основное тригонометрическое тождество $\sin^2\alpha + \cos^2\alpha = 1$:<br>$\cos^3\alpha + \sin^3\alpha = (\cos\alpha + \sin\alpha)(\cos^2\alpha - \cos\alpha\sin\alpha + \sin^2\alpha) = (\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha)$<br>Подставим это обратно в исходное выражение:<br>$(\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha)(\cos\alpha - \sin\alpha)$<br>Перегруппируем множители и применим формулу разности квадратов $(a+b)(a-b) = a^2-b^2$:<br>$(\cos\alpha - \sin\alpha)(\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha) = (\cos^2\alpha - \sin^2\alpha)(1 - \sin\alpha\cos\alpha)$<br>Выражение $\cos^2\alpha - \sin^2\alpha$ является формулой косинуса двойного угла $\cos 2\alpha$.<br>Таким образом, окончательное выражение:<br>$\cos 2\alpha(1 - \sin\alpha\cos\alpha)$<br>Ответ: $\cos 2\alpha(1 - \sin\alpha\cos\alpha)$</p><p><strong>в)</strong> Рассмотрим выражение $\sin^4\alpha + \cos^4\alpha - \frac{1}{4}\cos 4\alpha$.<br>Преобразуем сумму $\sin^4\alpha + \cos^4\alpha$, выделив полный квадрат:<br>$\sin^4\alpha + \cos^4\alpha = (\sin^2\alpha)^2 + (\cos^2\alpha)^2 = (\sin^2\alpha + \cos^2\alpha)^2 - 2\sin^2\alpha\cos^2\alpha$<br>Так как $\sin^2\alpha + \cos^2\alpha = 1$, получаем:<br>$= 1 - 2\sin^2\alpha\cos^2\alpha$<br>Теперь преобразуем $2\sin^2\alpha\cos^2\alpha$, используя формулу синуса двойного угла $\sin 2\alpha = 2\sin\alpha\cos\alpha$ :<br>$2\sin^2\alpha\cos^2\alpha = \frac{1}{2}(4\sin^2\alpha\cos^2\alpha) = \frac{1}{2}(2\sin\alpha\cos\alpha)^2 = \frac{1}{2}\sin^2(2\alpha)$<br>Итак, $\sin^4\alpha + \cos^4\alpha = 1 - \frac{1}{2}\sin^2(2\alpha)$.<br>Подставим это в исходное выражение:<br>$1 - \frac{1}{2}\sin^2(2\alpha) - \frac{1}{4}\cos 4\alpha$<br>Используем формулу понижения степени (или косинуса двойного угла) $\sin^2(2\alpha) = \frac{1 - \cos(4\alpha)}{2}$:<br>$= 1 - \frac{1}{2}\left(\frac{1 - \cos(4\alpha)}{2}\right) - \frac{1}{4}\cos 4\alpha = 1 - \frac{1 - \cos(4\alpha)}{4} - \frac{1}{4}\cos 4\alpha$<br>Раскроем скобки и приведем подобные члены:<br>$= 1 - \frac{1}{4} + \frac{\cos 4\alpha}{4} - \frac{\cos 4\alpha}{4} = \frac{3}{4}$<br>Ответ: $\frac{3}{4}$</p><p><strong>г)</strong> Для упрощения выражения $\cos^4\alpha - 6\cos^2\alpha \sin^2\alpha + \sin^4\alpha$ представим средний член $-6\cos^2\alpha\sin^2\alpha$ в виде суммы $-2\cos^2\alpha\sin^2\alpha - 4\cos^2\alpha\sin^2\alpha$ :<br>$\cos^4\alpha - 2\cos^2\alpha\sin^2\alpha + \sin^4\alpha - 4\cos^2\alpha\sin^2\alpha$<br>Первые три члена образуют полный квадрат разности:<br>$(\cos^2\alpha - \sin^2\alpha)^2 - 4\cos^2\alpha\sin^2\alpha$<br>Применим формулу косинуса двойного угла $\cos 2\alpha = \cos^2\alpha - \sin^2\alpha$ к первому члену и формулу синуса двойного угла $\sin 2\alpha = 2\sin\alpha\cos\alpha$ ко второму члену:<br>$(\cos 2\alpha)^2 - (2\sin\alpha\cos\alpha)^2 = \cos^2(2\alpha) - (\sin 2\alpha)^2 = \cos^2(2\alpha) - \sin^2(2\alpha)$<br>Полученное выражение снова является формулой косинуса двойного угла, но для угла $2\alpha$ :<br>$\cos(2 \cdot 2\alpha) = \cos 4\alpha$<br>Ответ: $\cos 4\alpha$</p>" ] #original: array:6 [ "id" => 1554330 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1152} "task" => array:2 [ "refs" => "1108470" "type" => "task" ] "text" => "<p><strong>а)</strong> Для упрощения выражения $16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha$ будем последовательно применять формулу синуса двойного угла $ \sin(2x) = 2\sin x \cos x $.<br>Сначала сгруппируем множители $\cos \alpha$ и $\sin \alpha$:<br>$16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha = 8\cos 4\alpha \cos 2\alpha (2\sin \alpha \cos \alpha)$<br>Применяя формулу, получаем $\sin 2\alpha$:<br>$= 8\cos 4\alpha \cos 2\alpha \sin 2\alpha$<br>Теперь сгруппируем $\cos 2\alpha$ и $\sin 2\alpha$:<br>$= 4\cos 4\alpha (2\sin 2\alpha \cos 2\alpha)$<br>Применяя формулу, получаем $\sin 4\alpha$:<br>$= 4\cos 4\alpha \sin 4\alpha$<br>И еще раз применяем ту же формулу:<br>$= 2(2\sin 4\alpha \cos 4\alpha) = 2\sin(2 \cdot 4\alpha) = 2\sin 8\alpha$<br>Ответ: $2\sin 8\alpha$</p><p><strong>б)</strong> В выражении $(\cos^3\alpha + \sin^3\alpha)(\cos \alpha - \sin \alpha)$ раскроем первую скобку, используя формулу суммы кубов $a^3+b^3=(a+b)(a^2-ab+b^2)$ и основное тригонометрическое тождество $\sin^2\alpha + \cos^2\alpha = 1$:<br>$\cos^3\alpha + \sin^3\alpha = (\cos\alpha + \sin\alpha)(\cos^2\alpha - \cos\alpha\sin\alpha + \sin^2\alpha) = (\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha)$<br>Подставим это обратно в исходное выражение:<br>$(\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha)(\cos\alpha - \sin\alpha)$<br>Перегруппируем множители и применим формулу разности квадратов $(a+b)(a-b) = a^2-b^2$:<br>$(\cos\alpha - \sin\alpha)(\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha) = (\cos^2\alpha - \sin^2\alpha)(1 - \sin\alpha\cos\alpha)$<br>Выражение $\cos^2\alpha - \sin^2\alpha$ является формулой косинуса двойного угла $\cos 2\alpha$.<br>Таким образом, окончательное выражение:<br>$\cos 2\alpha(1 - \sin\alpha\cos\alpha)$<br>Ответ: $\cos 2\alpha(1 - \sin\alpha\cos\alpha)$</p><p><strong>в)</strong> Рассмотрим выражение $\sin^4\alpha + \cos^4\alpha - \frac{1}{4}\cos 4\alpha$.<br>Преобразуем сумму $\sin^4\alpha + \cos^4\alpha$, выделив полный квадрат:<br>$\sin^4\alpha + \cos^4\alpha = (\sin^2\alpha)^2 + (\cos^2\alpha)^2 = (\sin^2\alpha + \cos^2\alpha)^2 - 2\sin^2\alpha\cos^2\alpha$<br>Так как $\sin^2\alpha + \cos^2\alpha = 1$, получаем:<br>$= 1 - 2\sin^2\alpha\cos^2\alpha$<br>Теперь преобразуем $2\sin^2\alpha\cos^2\alpha$, используя формулу синуса двойного угла $\sin 2\alpha = 2\sin\alpha\cos\alpha$ :<br>$2\sin^2\alpha\cos^2\alpha = \frac{1}{2}(4\sin^2\alpha\cos^2\alpha) = \frac{1}{2}(2\sin\alpha\cos\alpha)^2 = \frac{1}{2}\sin^2(2\alpha)$<br>Итак, $\sin^4\alpha + \cos^4\alpha = 1 - \frac{1}{2}\sin^2(2\alpha)$.<br>Подставим это в исходное выражение:<br>$1 - \frac{1}{2}\sin^2(2\alpha) - \frac{1}{4}\cos 4\alpha$<br>Используем формулу понижения степени (или косинуса двойного угла) $\sin^2(2\alpha) = \frac{1 - \cos(4\alpha)}{2}$:<br>$= 1 - \frac{1}{2}\left(\frac{1 - \cos(4\alpha)}{2}\right) - \frac{1}{4}\cos 4\alpha = 1 - \frac{1 - \cos(4\alpha)}{4} - \frac{1}{4}\cos 4\alpha$<br>Раскроем скобки и приведем подобные члены:<br>$= 1 - \frac{1}{4} + \frac{\cos 4\alpha}{4} - \frac{\cos 4\alpha}{4} = \frac{3}{4}$<br>Ответ: $\frac{3}{4}$</p><p><strong>г)</strong> Для упрощения выражения $\cos^4\alpha - 6\cos^2\alpha \sin^2\alpha + \sin^4\alpha$ представим средний член $-6\cos^2\alpha\sin^2\alpha$ в виде суммы $-2\cos^2\alpha\sin^2\alpha - 4\cos^2\alpha\sin^2\alpha$ :<br>$\cos^4\alpha - 2\cos^2\alpha\sin^2\alpha + \sin^4\alpha - 4\cos^2\alpha\sin^2\alpha$<br>Первые три члена образуют полный квадрат разности:<br>$(\cos^2\alpha - \sin^2\alpha)^2 - 4\cos^2\alpha\sin^2\alpha$<br>Применим формулу косинуса двойного угла $\cos 2\alpha = \cos^2\alpha - \sin^2\alpha$ к первому члену и формулу синуса двойного угла $\sin 2\alpha = 2\sin\alpha\cos\alpha$ ко второму члену:<br>$(\cos 2\alpha)^2 - (2\sin\alpha\cos\alpha)^2 = \cos^2(2\alpha) - (\sin 2\alpha)^2 = \cos^2(2\alpha) - \sin^2(2\alpha)$<br>Полученное выражение снова является формулой косинуса двойного угла, но для угла $2\alpha$ :<br>$\cos(2 \cdot 2\alpha) = \cos 4\alpha$<br>Ответ: $\cos 4\alpha$</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" => "1108471" "type" => "task" ] "previous" => array:2 [ "refs" => "1108469" "type" => "task" ] "book" => Illuminate\Database\Eloquent\Collection {#1090 #items: array:1 [ 0 => App\Models\Book {#1114} ] #escapeWhenCastingToString: false } "page" => Illuminate\Database\Eloquent\Collection {#1876 #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" => 1097950 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/page-208" "field_display_title" => "208" "field_folder" => "folder1" "field_image_name" => "208" "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 {#1109 #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 {#1101 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1098 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1100 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1073 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1087 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1092 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1091 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1150 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1153 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1154 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1155 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1156 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1157 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1158 …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 {#1159 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1160 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1161 …2} "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1162 …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 {#1101 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1098 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1100 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1073 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1087 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1092 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1091 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1150 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1153 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1154 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1155 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1156 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1157 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1158 …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 {#1159 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1160 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1161 …2} "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1162 …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 {#1163 #items: [] #escapeWhenCastingToString: false } "content" => Illuminate\Database\Eloquent\Collection {#1164 #items: array:1 [ 0 => 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" => 1261101 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1166 …2} "book_page" => array:2 [ …2] "img" => array:1 [ …1] ] #original: array:6 [ "id" => 1261101 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1166 …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" => "1097951" "type" => "book_page" ] "previous" => array:2 [ "refs" => "1097949" "type" => "book_page" ] "tasks" => Illuminate\Database\Eloquent\Collection {#1173 #items: array:7 [ 0 => App\Models\Task {#1174 #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" => 1108468 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-727" "field_display_title" => "727" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1175 …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 {#1177 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1178 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1211 …2} "content" => Illuminate\Database\Eloquent\Collection {#1248 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1273 …2} "page" => array:2 [ …2] ] #original: array:24 [ "id" => 1108468 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-727" "field_display_title" => "727" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1175 …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 {#1177 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1178 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1211 …2} "content" => Illuminate\Database\Eloquent\Collection {#1248 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1273 …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 {#1274 #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" => 1108469 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-728" "field_display_title" => "728" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1275 …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 {#1277 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1278 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1311 …2} "content" => Illuminate\Database\Eloquent\Collection {#1348 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1373 …2} "page" => array:2 [ …2] ] #original: array:24 [ "id" => 1108469 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-728" "field_display_title" => "728" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1275 …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 {#1277 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1278 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1311 …2} "content" => Illuminate\Database\Eloquent\Collection {#1348 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1373 …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 => "*" ] } 2 => App\Models\Task {#1374 #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" => 1108470 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-729" "field_display_title" => "729" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1375 …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 {#1377 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1378 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1411 …2} "content" => Illuminate\Database\Eloquent\Collection {#1448 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1473 …2} "page" => array:2 [ …2] ] #original: array:24 [ "id" => 1108470 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-729" "field_display_title" => "729" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1375 …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 {#1377 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1378 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1411 …2} "content" => Illuminate\Database\Eloquent\Collection {#1448 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1473 …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 => "*" ] } 3 => App\Models\Task {#1474 #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" => 1108471 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-730" "field_display_title" => "730" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1475 …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 {#1477 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1478 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1511 …2} "content" => Illuminate\Database\Eloquent\Collection {#1548 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1573 …2} "page" => array:2 [ …2] ] #original: array:24 [ "id" => 1108471 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-730" "field_display_title" => "730" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1475 …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 {#1477 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1478 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1511 …2} "content" => Illuminate\Database\Eloquent\Collection {#1548 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1573 …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 => "*" ] } 4 => App\Models\Task {#1574 #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" => 1108472 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-731" "field_display_title" => "731" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1575 …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 {#1577 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1578 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1611 …2} "content" => Illuminate\Database\Eloquent\Collection {#1648 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1673 …2} "page" => array:2 [ …2] ] #original: array:24 [ "id" => 1108472 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-731" "field_display_title" => "731" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1575 …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 {#1577 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1578 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1611 …2} "content" => Illuminate\Database\Eloquent\Collection {#1648 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1673 …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 => "*" ] } 5 => App\Models\Task {#1674 #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" => 1108473 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-732" "field_display_title" => "732" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1675 …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 {#1677 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1678 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1711 …2} "content" => Illuminate\Database\Eloquent\Collection {#1748 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1773 …2} "page" => array:2 [ …2] ] #original: array:24 [ "id" => 1108473 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-732" "field_display_title" => "732" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1675 …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 {#1677 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1678 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1711 …2} "content" => Illuminate\Database\Eloquent\Collection {#1748 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1773 …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 => "*" ] } 6 => App\Models\Task {#1774 #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" => 1108474 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-733" "field_display_title" => "733" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1775 …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 {#1777 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1778 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1811 …2} "content" => Illuminate\Database\Eloquent\Collection {#1848 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1873 …2} "page" => array:2 [ …2] ] #original: array:24 [ "id" => 1108474 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_page_end" => null "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/1-733" "field_display_title" => "733" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1775 …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 {#1777 …2} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1778 …2} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1811 …2} "content" => Illuminate\Database\Eloquent\Collection {#1848 …2} "next" => array:2 [ …2] "previous" => array:2 [ …2] "book" => Illuminate\Database\Eloquent\Collection {#1873 …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 => "*" ] } ] #escapeWhenCastingToString: false } ] #original: array:21 [ "id" => 1097950 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "208" "field_url" => "/9-klass/algebra/kokshetau-soltan-uchebnik/page-208" "field_display_title" => "208" "field_folder" => "folder1" "field_image_name" => "208" "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 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№729 (с. 208)
Условие. №729 (с. 208)
скриншот условия
729. Упростите выражение:
a) $16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha$;
б) $(\cos^3\alpha + \sin^3\alpha)(\cos \alpha - \sin \alpha)$;
в) $\sin^4\alpha + \cos^4\alpha - \frac{1}{4} \cos 4\alpha$;
г) $\cos^4\alpha - 6\cos^2\alpha \sin^2\alpha + \sin^4\alpha$.
Решение. №729 (с. 208)
Решение 2 (rus). №729 (с. 208)
а) Для упрощения выражения $16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha$ будем последовательно применять формулу синуса двойного угла $ \sin(2x) = 2\sin x \cos x $.
Сначала сгруппируем множители $\cos \alpha$ и $\sin \alpha$:
$16\cos 4\alpha \cos 2\alpha \cos \alpha \sin \alpha = 8\cos 4\alpha \cos 2\alpha (2\sin \alpha \cos \alpha)$
Применяя формулу, получаем $\sin 2\alpha$:
$= 8\cos 4\alpha \cos 2\alpha \sin 2\alpha$
Теперь сгруппируем $\cos 2\alpha$ и $\sin 2\alpha$:
$= 4\cos 4\alpha (2\sin 2\alpha \cos 2\alpha)$
Применяя формулу, получаем $\sin 4\alpha$:
$= 4\cos 4\alpha \sin 4\alpha$
И еще раз применяем ту же формулу:
$= 2(2\sin 4\alpha \cos 4\alpha) = 2\sin(2 \cdot 4\alpha) = 2\sin 8\alpha$
Ответ: $2\sin 8\alpha$
б) В выражении $(\cos^3\alpha + \sin^3\alpha)(\cos \alpha - \sin \alpha)$ раскроем первую скобку, используя формулу суммы кубов $a^3+b^3=(a+b)(a^2-ab+b^2)$ и основное тригонометрическое тождество $\sin^2\alpha + \cos^2\alpha = 1$:
$\cos^3\alpha + \sin^3\alpha = (\cos\alpha + \sin\alpha)(\cos^2\alpha - \cos\alpha\sin\alpha + \sin^2\alpha) = (\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha)$
Подставим это обратно в исходное выражение:
$(\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha)(\cos\alpha - \sin\alpha)$
Перегруппируем множители и применим формулу разности квадратов $(a+b)(a-b) = a^2-b^2$:
$(\cos\alpha - \sin\alpha)(\cos\alpha + \sin\alpha)(1 - \sin\alpha\cos\alpha) = (\cos^2\alpha - \sin^2\alpha)(1 - \sin\alpha\cos\alpha)$
Выражение $\cos^2\alpha - \sin^2\alpha$ является формулой косинуса двойного угла $\cos 2\alpha$.
Таким образом, окончательное выражение:
$\cos 2\alpha(1 - \sin\alpha\cos\alpha)$
Ответ: $\cos 2\alpha(1 - \sin\alpha\cos\alpha)$
в) Рассмотрим выражение $\sin^4\alpha + \cos^4\alpha - \frac{1}{4}\cos 4\alpha$.
Преобразуем сумму $\sin^4\alpha + \cos^4\alpha$, выделив полный квадрат:
$\sin^4\alpha + \cos^4\alpha = (\sin^2\alpha)^2 + (\cos^2\alpha)^2 = (\sin^2\alpha + \cos^2\alpha)^2 - 2\sin^2\alpha\cos^2\alpha$
Так как $\sin^2\alpha + \cos^2\alpha = 1$, получаем:
$= 1 - 2\sin^2\alpha\cos^2\alpha$
Теперь преобразуем $2\sin^2\alpha\cos^2\alpha$, используя формулу синуса двойного угла $\sin 2\alpha = 2\sin\alpha\cos\alpha$ :
$2\sin^2\alpha\cos^2\alpha = \frac{1}{2}(4\sin^2\alpha\cos^2\alpha) = \frac{1}{2}(2\sin\alpha\cos\alpha)^2 = \frac{1}{2}\sin^2(2\alpha)$
Итак, $\sin^4\alpha + \cos^4\alpha = 1 - \frac{1}{2}\sin^2(2\alpha)$.
Подставим это в исходное выражение:
$1 - \frac{1}{2}\sin^2(2\alpha) - \frac{1}{4}\cos 4\alpha$
Используем формулу понижения степени (или косинуса двойного угла) $\sin^2(2\alpha) = \frac{1 - \cos(4\alpha)}{2}$:
$= 1 - \frac{1}{2}\left(\frac{1 - \cos(4\alpha)}{2}\right) - \frac{1}{4}\cos 4\alpha = 1 - \frac{1 - \cos(4\alpha)}{4} - \frac{1}{4}\cos 4\alpha$
Раскроем скобки и приведем подобные члены:
$= 1 - \frac{1}{4} + \frac{\cos 4\alpha}{4} - \frac{\cos 4\alpha}{4} = \frac{3}{4}$
Ответ: $\frac{3}{4}$
г) Для упрощения выражения $\cos^4\alpha - 6\cos^2\alpha \sin^2\alpha + \sin^4\alpha$ представим средний член $-6\cos^2\alpha\sin^2\alpha$ в виде суммы $-2\cos^2\alpha\sin^2\alpha - 4\cos^2\alpha\sin^2\alpha$ :
$\cos^4\alpha - 2\cos^2\alpha\sin^2\alpha + \sin^4\alpha - 4\cos^2\alpha\sin^2\alpha$
Первые три члена образуют полный квадрат разности:
$(\cos^2\alpha - \sin^2\alpha)^2 - 4\cos^2\alpha\sin^2\alpha$
Применим формулу косинуса двойного угла $\cos 2\alpha = \cos^2\alpha - \sin^2\alpha$ к первому члену и формулу синуса двойного угла $\sin 2\alpha = 2\sin\alpha\cos\alpha$ ко второму члену:
$(\cos 2\alpha)^2 - (2\sin\alpha\cos\alpha)^2 = \cos^2(2\alpha) - (\sin 2\alpha)^2 = \cos^2(2\alpha) - \sin^2(2\alpha)$
Полученное выражение снова является формулой косинуса двойного угла, но для угла $2\alpha$ :
$\cos(2 \cdot 2\alpha) = \cos 4\alpha$
Ответ: $\cos 4\alpha$
Другие задания:
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