Номер 825, страница 201 - гдз по геометрии 10-11 класс учебник Атанасян, Бутузов

Геометрия, 10-11 класс Учебник, авторы: Атанасян Левон Сергеевич, Бутузов Валентин Фёдорович, Кадомцев Сергей Борисович, Позняк Эдуард Генрихович, Киселёва Людмила Сергеевна, издательство Просвещение, Москва, 2019, коричневого цвета

Авторы: Атанасян Л. С., Бутузов В. Ф., Кадомцев С. Б., Позняк Э. Г., Киселёва Л. С.

Тип: Учебник

Издательство: Просвещение

Год издания: 2019 - 2026

Уровень обучения: базовый и углублённый

Цвет обложки: коричневый с ромбами

ISBN: 978-5-09-103606-0 (2023)

Допущено Министерством просвещения Российской Федерации

Математика: алгебра и начала математического анализа, геометрия

Глава 8. Некоторые сведения из планиметрии. Параграф 1. Углы и отрезки, связанные с окружностью - номер 825, страница 201.

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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_foreign_lang_surname" => null
                            "field_name" => "Людмила"
                            "field_patronymic" => "Сергеевна"
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                          ]
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                          ]
                        }
                      ]
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                    }
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                      #items: []
                      #escapeWhenCastingToString: false
                    }
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                      #items: array:1 [
                        0 => App\Models\Term {#1065
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #attributes: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
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                          ]
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                            "updated_at" => null
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                      ]
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                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1066
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                        0 => App\Models\Term {#1067
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_translit" => "rossiya"
                          ]
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                      ]
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                    "field_city" => Illuminate\Database\Eloquent\Collection {#1068
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                        0 => App\Models\Term {#1069
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #withCount: []
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                          #perPage: 15
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                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
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                            "field_translit" => "moskva"
                          ]
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                      ]
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                    }
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                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1071
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1072
                      #items: array:1 [
                        0 => App\Models\Term {#1073
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #attributes: array:6 [
                            "id" => 41
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => array:6 [ …6]
                            "field_translit" => "bazovyy i uglublennyy"
                          ]
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                            "id" => 41
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => array:6 [ …6]
                            "field_translit" => "bazovyy i uglublennyy"
                          ]
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                        }
                      ]
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                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1074
                      #items: array:1 [
                        0 => App\Models\Term {#1075
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
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                          #attributes: array:10 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [ …6]
                            "field_color" => null
                            "field_end_year" => "2022"
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                          ]
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                            "id" => 6706
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                            "updated_at" => null
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                            "field_color" => null
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                          ]
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                      ]
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                    }
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1076
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                        0 => App\Models\Term {#1077
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #withCount: []
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                          #attributes: array:6 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "stereotipnoe"
                          ]
                          #original: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
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                          ]
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                      ]
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                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1078
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "с ромбами"
                    "field_publication_year" => "2019"
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                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для общеобразовательных организаций"
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                    "field_reserve_field" => "Математика: алгебра и начала математического анализа, геометрия"
                    "field_link_to_source" => null
                    "field_tasks_count" => "1147"
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                      0 => "/media/geometrija_10/atanasjan-u23/covers/cover1.webp?ts=1739363242"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
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                      0 => array:4 [
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                        "alt" => ""
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                      ]
                    ]
                    "field_popular_book" => null
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1079
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1080
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1081
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/10-klass/geometrija/atanasjan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1082
                      #items: array:1 [
                        0 => App\Models\Term {#1083
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #withCount: []
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                          #attributes: array:6 [
                            "id" => 51
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "коричневый"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "korichnevyy"
                          ]
                          #original: array:6 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "коричневый"
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                            "field_translit" => "korichnevyy"
                          ]
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                      ]
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                    ]
                  ]
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                    "created_at" => "2026-04-10 13:58:26"
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                    "field_tree_default_status" => "tasks"
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1052}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1055}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1057}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1063}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1064}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1066}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1068}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1070}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1071}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1072}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1074}
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1076}
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                    "field_cover_description" => "с ромбами"
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                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для общеобразовательных организаций"
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                    "field_link_to_source" => null
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                      0 => "/media/geometrija_10/atanasjan-u23/covers/cover1.webp?ts=1739363242"
                    ]
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                    ]
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                      ]
                    ]
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                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1080}
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                    "field_url" => "/10-klass/geometrija/atanasjan-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1082}
                    "field_metatags_title" => null
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                    ]
                  ]
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                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1084
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 744411
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Некоторые сведения из планиметрии"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1050}
            "field_page_start" => "194"
            "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
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1086}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1084}
          ]
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            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1121
      #items: array:2 [
        0 => App\Models\Branch {#1129
          #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" => 744411
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Некоторые сведения из планиметрии"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1130
              #items: array:1 [
                0 => App\Models\Term {#1047}
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "194"
            "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 {#1131
              #items: array:1 [
                0 => App\Models\Book {#1049}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1132
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 744411
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Некоторые сведения из планиметрии"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1130}
            "field_page_start" => "194"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
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            "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 {#1131}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1132}
          ]
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          #dateFormat: null
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          +timestamps: true
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1133
          #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" => 744412
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Углы и отрезки, связанные с окружностью"
            "field_branch_order" => "1"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1137
              #items: array:1 [
                0 => App\Models\Term {#1134
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #original: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
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                    0 => "*"
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                }
              ]
              #escapeWhenCastingToString: false
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            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1136
              #items: array:1 [
                0 => App\Models\Book {#1049}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1135
              #items: array:1 [
                0 => App\Models\Branch {#1045}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 744412
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Углы и отрезки, связанные с окружностью"
            "field_branch_order" => "1"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1137}
            "field_page_start" => "194"
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            "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}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1135}
          ]
          #changes: []
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          #attributeCastCache: []
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          +timestamps: true
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          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1038
      #items: array:4 [
        0 => App\Models\Element {#1111
          #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" => 940125
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1100
              #items: array:1 [
                0 => App\Models\Edition {#1108
                  #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" => 2315
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1106 …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 {#1107 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1105 …2}
                    "field_process_formula" => "wiris"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1104 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 2315
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1106 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
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                    "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 {#1107 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1105 …2}
                    "field_process_formula" => "wiris"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1104 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #touches: []
                  +timestamps: true
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                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "745240"
              "type" => "task"
            ]
            "text" => "<p> <b>825.</b> Хорды <i>АВ</i> и <i>СD</i> взаимно перпендикулярны , луч <i>АВ</i> является биссектрисой угла DАЕ. Докажите, что <span class="long">АЕ ⊥ ВС.</span> Рассмотрите все возможные случаи. </p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "825-1.jpg"
                "alt" => null
                "width" => "1064"
                "height" => 228
                "path" => "/media/geometrija_10/atanasjan-u23/0-00/825-1.webp?ts=1739436917"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 940125
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1100}
            "task" => array:2 [
              "refs" => "745240"
              "type" => "task"
            ]
            "text" => "<p> <b>825.</b> Хорды <i>АВ</i> и <i>СD</i> взаимно перпендикулярны , луч <i>АВ</i> является биссектрисой угла DАЕ. Докажите, что <span class="long">АЕ ⊥ ВС.</span> Рассмотрите все возможные случаи. </p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "825-1.jpg"
                "alt" => null
                "width" => "1064"
                "height" => 228
                "path" => "/media/geometrija_10/atanasjan-u23/0-00/825-1.webp?ts=1739436917"
              ]
            ]
          ]
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          #attributeCastCache: []
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          #touches: []
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          #hidden: []
          #visible: []
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          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1096
          #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" => 942786
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1043
              #items: array:1 [
                0 => App\Models\Edition {#1095
                  #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" => 2317
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 2"
                    "field_order" => "3"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1092 …2}
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                    "field_edition_type" => "solution"
                    "field_root_dir" => "2-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1089 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1090 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1085 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 2317
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 2"
                    "field_order" => "3"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1092 …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" => "2-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1089 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1090 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1085 …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" => "745240"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "825-1.png"
                "alt" => null
                "width" => "694"
                "height" => 3388
                "path" => "/media/geometrija_10/atanasjan-u23/2-00/825-1.webp?ts=1739441717"
              ]
            ]
          ]
          #original: array:6 [
            "id" => 942786
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1043}
            "task" => array:2 [
              "refs" => "745240"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "825-1.png"
                "alt" => null
                "width" => "694"
                "height" => 3388
                "path" => "/media/geometrija_10/atanasjan-u23/2-00/825-1.webp?ts=1739441717"
              ]
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          ]
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          #attributeCastCache: []
          #dateFormat: null
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          #touches: []
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          #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" => 942502
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1094
              #items: array:1 [
                0 => App\Models\Edition {#1103
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 2318
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 3"
                    "field_order" => "4"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1098 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "image"
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                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Неизвестный"
                    "field_moderator" => "pasha"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "3-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1097 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1091 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 2318
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 3"
                    "field_order" => "4"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1098 …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" => "3-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1097 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1091 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #dispatchesEvents: []
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                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "745240"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "825-1.jpg"
                "alt" => null
                "width" => "1413"
                "height" => 189
                "path" => "/media/geometrija_10/atanasjan-u23/3-00/825-1.webp?ts=1739437220"
              ]
            ]
          ]
          #original: array:6 [
            "id" => 942502
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1094}
            "task" => array:2 [
              "refs" => "745240"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "825-1.jpg"
                "alt" => null
                "width" => "1413"
                "height" => 189
                "path" => "/media/geometrija_10/atanasjan-u23/3-00/825-1.webp?ts=1739437220"
              ]
            ]
          ]
          #changes: []
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          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
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          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        3 => App\Models\Element {#1088
          #connection: "mysql"
          #table: "elements"
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            "text" => "<p>Для доказательства утверждения воспользуемся свойствами вписанных углов и дуг окружности, на которые они опираются.</p><p>Пусть все точки A, B, C, D, E лежат на одной окружности.По условию, луч AB является биссектрисой угла DAE. Углы ?DAB и ?EAB являются вписанными в окружность. Так как эти углы равны (?DAB = ?EAB), то и дуги, на которые они опираются, равны.Угол ?DAB опирается на дугу DB, а угол ?EAB опирается на дугу EB. Следовательно, величины этих дуг равны:$?DB = ?EB$</p><p>По условию, хорды AB и CD взаимно перпендикулярны. Пусть они пересекаются в точке P. Угол между пересекающимися хордами равен полусумме дуг, заключенных между его сторонами и сторонами вертикального ему угла. Для угла ?APC = 90° это означает:$?APC = \frac{1}{2} (?AC + ?DB)$Так как $?APC = 90°$, то получаем:$90° = \frac{1}{2} (?AC + ?DB)$Отсюда следует, что сумма дуг $?AC$ и $?DB$ равна $180°$:$?AC + ?DB = 180°$</p><p>Теперь рассмотрим угол между хордами AE и BC. Пусть они пересекаются в точке Q. Величина угла ?AQC также равна полусумме дуг, заключенных между его сторонами:$?AQC = \frac{1}{2} (?AC + ?EB)$Мы уже установили, что $?EB = ?DB$. Заменим в формуле дугу $?EB$ на равную ей дугу $?DB$:$?AQC = \frac{1}{2} (?AC + ?DB)$А так как мы ранее вывели, что $?AC + ?DB = 180°$, то получаем:$?AQC = \frac{1}{2} (180°) = 90°$Угол между хордами AE и BC равен 90°, что означает, что они перпендикулярны: $AE \perp BC$.Что и требовалось доказать.</p><p>Рассмотрим все возможные случаи, упомянутые в условии задачи.</p><p>Прежде всего, докажем, что точка пересечения P хорд AB и CD должна лежать внутри окружности. Если бы линии, содержащие хорды, пересекались вне окружности в точке P, то угол между ними вычислялся бы как полуразность дуг: $?P = \frac{1}{2} (?AC - ?BD) = 90°$. Отсюда $?AC - ?BD = 180°$, что невозможно, так как большая из двух вычитаемых дуг (в данном случае $?AC$) не может превышать $180°$ (если считать ее меньшей дугой), а если она является большей дугой, то ее величина будет больше $180°$, но тогда разность будет еще больше. Таким образом, пересечение хорд может быть только внутренним.</p><p><strong>Частный случай 1: Одна из хорд, например AB, является диаметром.</strong>Если AB — диаметр и $AB \perp CD$, то AB делит хорду CD и дуги, которые она стягивает, пополам. В частности, $?BC = ?BD$.Из условия, что луч AB — биссектриса угла ?DAE, следует, что $?DB = ?EB$.Из этих двух равенств получаем, что $?BC = ?EB$. Поскольку у этих дуг есть общая точка B, их вторые концы должны совпадать, то есть точка E совпадает с точкой C.Задача сводится к доказательству, что $AC \perp BC$. Это известное свойство окружности: вписанный угол ?ACB, опирающийся на диаметр AB, является прямым. Следовательно, $AC \perp BC$.</p><p><strong>Частный случай 2: Хорда CD является диаметром.</strong>Если CD — диаметр и $AB \perp CD$, то диаметр CD делит хорду AB и стягиваемую ею дугу пополам, то есть $?AD = ?BD$ и $?AC = ?BC$.Из условия, что луч AB — биссектриса угла ?DAE, следует, что $?DB = ?EB$.Из равенств $?AD = ?BD$ и $?DB = ?EB$ получаем $?AD = ?EB$.Мы должны доказать, что $AE \perp BC$, то есть что сумма дуг $?AC + ?EB$ равна $180°$.Заменим в этой сумме $?AC$ на $?BC$ и $?EB$ на $?AD$:$?AC + ?EB = ?BC + ?AD$Поскольку CD — диаметр, дуга CBD является полуокружностью, то есть $?CB + ?BD = 180°$.Так как $?AD = ?BD$, то $?CB + ?AD = 180°$.Следовательно, $?AC + ?EB = 180°$, и угол между хордами AE и BC равен $90°$.</p><p>Таким образом, общее доказательство, приведенное вначале, корректно для всех возможных конфигураций, включая частные случаи, когда одна из хорд является диаметром.</p><p><strong>Ответ:</strong> Утверждение доказано. Во всех возможных случаях $AE \perp BC$.</p>"
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            "id" => 1352553
            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1122}
            "task" => array:2 [
              "refs" => "745240"
              "type" => "task"
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            "text" => "<p>Для доказательства утверждения воспользуемся свойствами вписанных углов и дуг окружности, на которые они опираются.</p><p>Пусть все точки A, B, C, D, E лежат на одной окружности.По условию, луч AB является биссектрисой угла DAE. Углы ?DAB и ?EAB являются вписанными в окружность. Так как эти углы равны (?DAB = ?EAB), то и дуги, на которые они опираются, равны.Угол ?DAB опирается на дугу DB, а угол ?EAB опирается на дугу EB. Следовательно, величины этих дуг равны:$?DB = ?EB$</p><p>По условию, хорды AB и CD взаимно перпендикулярны. Пусть они пересекаются в точке P. Угол между пересекающимися хордами равен полусумме дуг, заключенных между его сторонами и сторонами вертикального ему угла. Для угла ?APC = 90° это означает:$?APC = \frac{1}{2} (?AC + ?DB)$Так как $?APC = 90°$, то получаем:$90° = \frac{1}{2} (?AC + ?DB)$Отсюда следует, что сумма дуг $?AC$ и $?DB$ равна $180°$:$?AC + ?DB = 180°$</p><p>Теперь рассмотрим угол между хордами AE и BC. Пусть они пересекаются в точке Q. Величина угла ?AQC также равна полусумме дуг, заключенных между его сторонами:$?AQC = \frac{1}{2} (?AC + ?EB)$Мы уже установили, что $?EB = ?DB$. Заменим в формуле дугу $?EB$ на равную ей дугу $?DB$:$?AQC = \frac{1}{2} (?AC + ?DB)$А так как мы ранее вывели, что $?AC + ?DB = 180°$, то получаем:$?AQC = \frac{1}{2} (180°) = 90°$Угол между хордами AE и BC равен 90°, что означает, что они перпендикулярны: $AE \perp BC$.Что и требовалось доказать.</p><p>Рассмотрим все возможные случаи, упомянутые в условии задачи.</p><p>Прежде всего, докажем, что точка пересечения P хорд AB и CD должна лежать внутри окружности. Если бы линии, содержащие хорды, пересекались вне окружности в точке P, то угол между ними вычислялся бы как полуразность дуг: $?P = \frac{1}{2} (?AC - ?BD) = 90°$. Отсюда $?AC - ?BD = 180°$, что невозможно, так как большая из двух вычитаемых дуг (в данном случае $?AC$) не может превышать $180°$ (если считать ее меньшей дугой), а если она является большей дугой, то ее величина будет больше $180°$, но тогда разность будет еще больше. Таким образом, пересечение хорд может быть только внутренним.</p><p><strong>Частный случай 1: Одна из хорд, например AB, является диаметром.</strong>Если AB — диаметр и $AB \perp CD$, то AB делит хорду CD и дуги, которые она стягивает, пополам. В частности, $?BC = ?BD$.Из условия, что луч AB — биссектриса угла ?DAE, следует, что $?DB = ?EB$.Из этих двух равенств получаем, что $?BC = ?EB$. Поскольку у этих дуг есть общая точка B, их вторые концы должны совпадать, то есть точка E совпадает с точкой C.Задача сводится к доказательству, что $AC \perp BC$. Это известное свойство окружности: вписанный угол ?ACB, опирающийся на диаметр AB, является прямым. Следовательно, $AC \perp BC$.</p><p><strong>Частный случай 2: Хорда CD является диаметром.</strong>Если CD — диаметр и $AB \perp CD$, то диаметр CD делит хорду AB и стягиваемую ею дугу пополам, то есть $?AD = ?BD$ и $?AC = ?BC$.Из условия, что луч AB — биссектриса угла ?DAE, следует, что $?DB = ?EB$.Из равенств $?AD = ?BD$ и $?DB = ?EB$ получаем $?AD = ?EB$.Мы должны доказать, что $AE \perp BC$, то есть что сумма дуг $?AC + ?EB$ равна $180°$.Заменим в этой сумме $?AC$ на $?BC$ и $?EB$ на $?AD$:$?AC + ?EB = ?BC + ?AD$Поскольку CD — диаметр, дуга CBD является полуокружностью, то есть $?CB + ?BD = 180°$.Так как $?AD = ?BD$, то $?CB + ?AD = 180°$.Следовательно, $?AC + ?EB = 180°$, и угол между хордами AE и BC равен $90°$.</p><p>Таким образом, общее доказательство, приведенное вначале, корректно для всех возможных конфигураций, включая частные случаи, когда одна из хорд является диаметром.</p><p><strong>Ответ:</strong> Утверждение доказано. Во всех возможных случаях $AE \perp BC$.</p>"
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                    "edition" => Illuminate\Database\Eloquent\Collection {#1145 …2}
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                  #connection: "mysql"
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№825 (с. 201)
Условие. №825 (с. 201)
скриншот условия
Геометрия, 10-11 класс Учебник, авторы: Атанасян Левон Сергеевич, Бутузов Валентин Фёдорович, Кадомцев Сергей Борисович, Позняк Эдуард Генрихович, Киселёва Людмила Сергеевна, издательство Просвещение, Москва, 2019, коричневого цвета, страница 201, номер 825, Условие

825. Хорды АВ и СD взаимно перпендикулярны , луч АВ является биссектрисой угла DАЕ. Докажите, что АЕ ⊥ ВС. Рассмотрите все возможные случаи.

Решение 2. №825 (с. 201)
Геометрия, 10-11 класс Учебник, авторы: Атанасян Левон Сергеевич, Бутузов Валентин Фёдорович, Кадомцев Сергей Борисович, Позняк Эдуард Генрихович, Киселёва Людмила Сергеевна, издательство Просвещение, Москва, 2019, коричневого цвета, страница 201, номер 825, Решение 2
Решение 3. №825 (с. 201)
Геометрия, 10-11 класс Учебник, авторы: Атанасян Левон Сергеевич, Бутузов Валентин Фёдорович, Кадомцев Сергей Борисович, Позняк Эдуард Генрихович, Киселёва Людмила Сергеевна, издательство Просвещение, Москва, 2019, коричневого цвета, страница 201, номер 825, Решение 3
Решение 6. №825 (с. 201)

Для доказательства утверждения воспользуемся свойствами вписанных углов и дуг окружности, на которые они опираются.

Пусть все точки A, B, C, D, E лежат на одной окружности.По условию, луч AB является биссектрисой угла DAE. Углы ?DAB и ?EAB являются вписанными в окружность. Так как эти углы равны (?DAB = ?EAB), то и дуги, на которые они опираются, равны.Угол ?DAB опирается на дугу DB, а угол ?EAB опирается на дугу EB. Следовательно, величины этих дуг равны:$?DB = ?EB$

По условию, хорды AB и CD взаимно перпендикулярны. Пусть они пересекаются в точке P. Угол между пересекающимися хордами равен полусумме дуг, заключенных между его сторонами и сторонами вертикального ему угла. Для угла ?APC = 90° это означает:$?APC = \frac{1}{2} (?AC + ?DB)$Так как $?APC = 90°$, то получаем:$90° = \frac{1}{2} (?AC + ?DB)$Отсюда следует, что сумма дуг $?AC$ и $?DB$ равна $180°$:$?AC + ?DB = 180°$

Теперь рассмотрим угол между хордами AE и BC. Пусть они пересекаются в точке Q. Величина угла ?AQC также равна полусумме дуг, заключенных между его сторонами:$?AQC = \frac{1}{2} (?AC + ?EB)$Мы уже установили, что $?EB = ?DB$. Заменим в формуле дугу $?EB$ на равную ей дугу $?DB$:$?AQC = \frac{1}{2} (?AC + ?DB)$А так как мы ранее вывели, что $?AC + ?DB = 180°$, то получаем:$?AQC = \frac{1}{2} (180°) = 90°$Угол между хордами AE и BC равен 90°, что означает, что они перпендикулярны: $AE \perp BC$.Что и требовалось доказать.

Рассмотрим все возможные случаи, упомянутые в условии задачи.

Прежде всего, докажем, что точка пересечения P хорд AB и CD должна лежать внутри окружности. Если бы линии, содержащие хорды, пересекались вне окружности в точке P, то угол между ними вычислялся бы как полуразность дуг: $?P = \frac{1}{2} (?AC - ?BD) = 90°$. Отсюда $?AC - ?BD = 180°$, что невозможно, так как большая из двух вычитаемых дуг (в данном случае $?AC$) не может превышать $180°$ (если считать ее меньшей дугой), а если она является большей дугой, то ее величина будет больше $180°$, но тогда разность будет еще больше. Таким образом, пересечение хорд может быть только внутренним.

Частный случай 1: Одна из хорд, например AB, является диаметром.Если AB — диаметр и $AB \perp CD$, то AB делит хорду CD и дуги, которые она стягивает, пополам. В частности, $?BC = ?BD$.Из условия, что луч AB — биссектриса угла ?DAE, следует, что $?DB = ?EB$.Из этих двух равенств получаем, что $?BC = ?EB$. Поскольку у этих дуг есть общая точка B, их вторые концы должны совпадать, то есть точка E совпадает с точкой C.Задача сводится к доказательству, что $AC \perp BC$. Это известное свойство окружности: вписанный угол ?ACB, опирающийся на диаметр AB, является прямым. Следовательно, $AC \perp BC$.

Частный случай 2: Хорда CD является диаметром.Если CD — диаметр и $AB \perp CD$, то диаметр CD делит хорду AB и стягиваемую ею дугу пополам, то есть $?AD = ?BD$ и $?AC = ?BC$.Из условия, что луч AB — биссектриса угла ?DAE, следует, что $?DB = ?EB$.Из равенств $?AD = ?BD$ и $?DB = ?EB$ получаем $?AD = ?EB$.Мы должны доказать, что $AE \perp BC$, то есть что сумма дуг $?AC + ?EB$ равна $180°$.Заменим в этой сумме $?AC$ на $?BC$ и $?EB$ на $?AD$:$?AC + ?EB = ?BC + ?AD$Поскольку CD — диаметр, дуга CBD является полуокружностью, то есть $?CB + ?BD = 180°$.Так как $?AD = ?BD$, то $?CB + ?AD = 180°$.Следовательно, $?AC + ?EB = 180°$, и угол между хордами AE и BC равен $90°$.

Таким образом, общее доказательство, приведенное вначале, корректно для всех возможных конфигураций, включая частные случаи, когда одна из хорд является диаметром.

Ответ: Утверждение доказано. Во всех возможных случаях $AE \perp BC$.

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