Номер 784, страница 191 - 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 7. Метод координат в пространстве. Движения. Параграф 3. Движения, дополнительные задачи - номер 784, страница 191.

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                            0 => "*"
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                        1 => App\Models\Term {#1136
                          #connection: "mysql"
                          #table: "terms"
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                            "created_at" => "2026-04-10 13:58:26"
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                            "field_cases" => array:6 [ …6]
                            "field_translit" => "odinadcatyj"
                          ]
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                            "id" => 5460
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "11"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "odinadcatyj"
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                      ]
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1137
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                        0 => App\Models\Term {#1138
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                          #attributes: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => null
                            "field_translit" => "prosveschenie"
                          ]
                          #original: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Просвещение"
                            "field_cases" => null
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                    "field_author" => Illuminate\Database\Eloquent\Collection {#1139
                      #items: array:5 [
                        0 => App\Models\Term {#1140
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #attributes: array:12 [
                            "id" => 3753
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Атанасян"
                             …8
                          ]
                          #original: array:12 [ …12]
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                          #guarded: array:1 [ …1]
                        }
                        1 => App\Models\Term {#1141
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
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                          #attributes: array:12 [ …12]
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                          #guarded: array:1 [ …1]
                        }
                        2 => App\Models\Term {#1142
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #fillable: []
                          #guarded: array:1 [ …1]
                        }
                        3 => App\Models\Term {#1143
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #guarded: array:1 [ …1]
                        }
                        4 => App\Models\Term {#1144
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
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                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1146
                      #items: array:1 [
                        0 => App\Models\Term {#1147
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                        }
                      ]
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                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1148
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                        0 => App\Models\Term {#1149
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                          #table: "terms"
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                          #keyType: "int"
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                        }
                      ]
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                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1150
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                          #table: "terms"
                          #primaryKey: "id"
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                        }
                      ]
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                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1152
                      #items: []
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                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1153
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1154
                      #items: array:1 [
                        0 => App\Models\Term {#1155
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                        }
                      ]
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                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1156
                      #items: array:1 [
                        0 => App\Models\Term {#1157
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                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #withCount: []
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                          #attributes: array:10 [ …10]
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                        }
                      ]
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                    }
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1158
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                        0 => App\Models\Term {#1159
                          #connection: "mysql"
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                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1160
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                    }
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                    "field_cover_description" => "с ромбами"
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                    "field_part" => ""
                    "field_part_writing" => ""
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                    "field_for_whom" => "Учебник для общеобразовательных организаций"
                    "field_allowed" => "Допущено Министерством просвещения Российской Федерации"
                    "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"
                    ]
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                      0 => ""
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                      0 => array:4 [
                        "path" => "/media/geometrija_10/atanasjan-u23/covers/cover1.webp?ts=1739363242"
                        "alt" => ""
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                      #items: []
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                    }
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                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1164
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                        0 => App\Models\Term {#1165
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                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1146}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1148}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1150}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1152}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1153}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1154}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1156}
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                      ]
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                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1164}
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1166
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            "field_display_title" => "Метод координат в пространстве. Движения"
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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 {#1168}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1166}
          ]
          #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 {#1167
          #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" => 744410
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Движения, дополнительные задачи"
            "field_branch_order" => "3"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1172
              #items: array:1 [
                0 => App\Models\Term {#1169
                  #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" => "§"
                  ]
                  #changes: []
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                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
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                  #dispatchesEvents: []
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "187"
            "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 {#1171
              #items: array:1 [
                0 => App\Models\Book {#1131}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1170
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 744410
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Движения, дополнительные задачи"
            "field_branch_order" => "3"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1172}
            "field_page_start" => "187"
            "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 {#1171}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1170}
          ]
          #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 {#1077
      #items: array:4 [
        0 => App\Models\Element {#1110
          #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" => 939914
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1099
              #items: array:1 [
                0 => App\Models\Edition {#1107
                  #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 {#1105 …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 {#1106 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1104 …2}
                    "field_process_formula" => "wiris"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1103 …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 {#1105 …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 {#1106 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1104 …2}
                    "field_process_formula" => "wiris"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1103 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "745199"
              "type" => "task"
            ]
            "text" => "<p> <b>784.</b> Отрезки <i>AB</i> и <i>CD</i> перемещаются по скрещивающимся прямым. Докажите, что объём тетраэдра <i>ABCD</i> при этом не изменяется. </p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "784-1.jpg"
                "alt" => null
                "width" => "1559"
                "height" => 169
                "path" => "/media/geometrija_10/atanasjan-u23/0-00/784-1.webp?ts=1739436900"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 939914
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1099}
            "task" => array:2 [
              "refs" => "745199"
              "type" => "task"
            ]
            "text" => "<p> <b>784.</b> Отрезки <i>AB</i> и <i>CD</i> перемещаются по скрещивающимся прямым. Докажите, что объём тетраэдра <i>ABCD</i> при этом не изменяется. </p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "784-1.jpg"
                "alt" => null
                "width" => "1559"
                "height" => 169
                "path" => "/media/geometrija_10/atanasjan-u23/0-00/784-1.webp?ts=1739436900"
              ]
            ]
          ]
          #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 => "*"
          ]
        }
        1 => App\Models\Element {#1095
          #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" => 942745
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1083
              #items: array:1 [
                0 => App\Models\Edition {#1094
                  #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 {#1091 …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 {#1088 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1089 …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 {#1091 …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 {#1088 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1089 …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" => "745199"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "784-1.png"
                "alt" => null
                "width" => "694"
                "height" => 5262
                "path" => "/media/geometrija_10/atanasjan-u23/2-00/784-1.webp?ts=1739441698"
              ]
            ]
          ]
          #original: array:6 [
            "id" => 942745
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1083}
            "task" => array:2 [
              "refs" => "745199"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "784-1.png"
                "alt" => null
                "width" => "694"
                "height" => 5262
                "path" => "/media/geometrija_10/atanasjan-u23/2-00/784-1.webp?ts=1739441698"
              ]
            ]
          ]
          #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 => "*"
          ]
        }
        2 => App\Models\Element {#1101
          #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" => 942491
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1093
              #items: array:1 [
                0 => App\Models\Edition {#1102
                  #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" => 2318
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 3"
                    "field_order" => "4"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1097 …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 {#1098 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1096 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1090 …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 {#1097 …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 {#1098 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1096 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1090 …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" => "745199"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "784-1.jpg"
                "alt" => null
                "width" => "1413"
                "height" => 773
                "path" => "/media/geometrija_10/atanasjan-u23/3-00/784-1.webp?ts=1739437220"
              ]
            ]
          ]
          #original: array:6 [
            "id" => 942491
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1093}
            "task" => array:2 [
              "refs" => "745199"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "784-1.jpg"
                "alt" => null
                "width" => "1413"
                "height" => 773
                "path" => "/media/geometrija_10/atanasjan-u23/3-00/784-1.webp?ts=1739437220"
              ]
            ]
          ]
          #changes: []
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          #classCastCache: []
          #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 => "*"
          ]
        }
        3 => App\Models\Element {#1087
          #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" => 1352512
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1121
              #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" => 5120
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 6"
                    "field_order" => "7"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1080 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "vadim"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "6-"
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            "text" => "<p>Для решения этой задачи воспользуемся формулой для вычисления объёма тетраэдра через длины двух его скрещивающихся рёбер, расстояние между ними и угол между ними.</p><p>Пусть отрезки $AB$ и $CD$ лежат на скрещивающихся прямых $l_1$ и $l_2$ соответственно. Объём тетраэдра $ABCD$ можно выразить через векторы его рёбер. Стандартная формула для объёма через смешанное произведение векторов, выходящих из одной вершины (например, $A$), имеет вид:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{AD}|$</p><p>Преобразуем это выражение, чтобы использовать векторы скрещивающихся рёбер $\vec{AB}$ и $\vec{CD}$. Заметим, что $\vec{AD} = \vec{AC} + \vec{CD}$. Подставим это в формулу:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot (\vec{AC} + \vec{CD})|$</p><p>Используя свойство дистрибутивности скалярного произведения, получаем:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{AC} + (\vec{AB} \times \vec{AC}) \cdot \vec{CD}|$</p><p>Смешанное произведение $(\vec{AB} \times \vec{AC}) \cdot \vec{AC}$ равно нулю, так как векторное произведение $(\vec{AB} \times \vec{AC})$ перпендикулярно вектору $\vec{AC}$, а скалярное произведение перпендикулярных векторов равно нулю. Таким образом, формула для объёма упрощается:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{CD}|$</p><p>Используя циклическую перестановку векторов в смешанном произведении, которая не меняет его модуля, получим:</p><p>$V = \frac{1}{6} |(\vec{AC} \times \vec{CD}) \cdot \vec{AB}|$</p><p>Теперь рассмотрим геометрический смысл этого выражения.Пусть $a = |\vec{AB}|$ и $b = |\vec{CD}|$ — длины отрезков $AB$ и $CD$. По условию задачи, эти длины постоянны.Пусть $\alpha$ — угол между скрещивающимися прямыми $l_1$ и $l_2$. Так как прямые зафиксированы, угол $\alpha$ является постоянной величиной. Этот угол равен углу между векторами $\vec{AB}$ и $\vec{CD}$.Пусть $d$ — расстояние между прямыми $l_1$ и $l_2$. Это расстояние также является постоянным.</p><p>Смешанное произведение $|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}|$ можно интерпретировать как объём параллелепипеда, построенного на векторах $\vec{AB}$, $\vec{CD}$ и $\vec{AC}$.Величина векторного произведения $|\vec{AB} \times \vec{CD}|$ равна $a \cdot b \cdot \sin\alpha$. Вектор $\vec{n} = \vec{AB} \times \vec{CD}$ перпендикулярен обеим прямым $l_1$ и $l_2$.</p><p>Тогда $|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}| = | \vec{n} \cdot \vec{AC} |$. Скалярное произведение $\vec{n} \cdot \vec{AC}$ представляет собой произведение модуля вектора $\vec{n}$ на проекцию вектора $\vec{AC}$ на направление вектора $\vec{n}$. Проекция вектора $\vec{AC}$ (соединяющего точку на $l_1$ с точкой на $l_2$) на направление, перпендикулярное обеим прямым, как раз и является расстоянием $d$ между этими прямыми.</p><p>Таким образом:</p><p>$|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}| = |\vec{AB} \times \vec{CD}| \cdot d = (a \cdot b \cdot \sin\alpha) \cdot d$</p><p>Подставляя это в формулу для объёма, получаем:</p><p>$V = \frac{1}{6} a \cdot b \cdot d \cdot \sin\alpha$</p><p>Проанализируем полученную формулу в контексте задачи:</p><ul><li>$a = |AB|$ — длина отрезка $AB$, которая по условию постоянна.</li> <li>$b = |CD|$ — длина отрезка $CD$, которая по условию постоянна.</li> <li>$l_1$ и $l_2$ — фиксированные скрещивающиеся прямые, поэтому расстояние $d$ между ними постоянно.</li> <li>Угол $\alpha$ между фиксированными прямыми $l_1$ и $l_2$ также постоянен.</li></ul><p>Поскольку все величины в правой части формулы ($a, b, d, \alpha$) являются константами, объём тетраэдра $V$ также является постоянной величиной и не зависит от положения отрезков $AB$ и $CD$ на своих прямых.</p><p>Что и требовалось доказать.</p><p><b>Ответ:</b> Объём тетраэдра $ABCD$ не изменяется, так как он зависит только от длин отрезков $AB$ и $CD$, а также от расстояния и угла между скрещивающимися прямыми, на которых они лежат. Все эти величины в условиях задачи постоянны.</p>"
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            "text" => "<p>Для решения этой задачи воспользуемся формулой для вычисления объёма тетраэдра через длины двух его скрещивающихся рёбер, расстояние между ними и угол между ними.</p><p>Пусть отрезки $AB$ и $CD$ лежат на скрещивающихся прямых $l_1$ и $l_2$ соответственно. Объём тетраэдра $ABCD$ можно выразить через векторы его рёбер. Стандартная формула для объёма через смешанное произведение векторов, выходящих из одной вершины (например, $A$), имеет вид:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{AD}|$</p><p>Преобразуем это выражение, чтобы использовать векторы скрещивающихся рёбер $\vec{AB}$ и $\vec{CD}$. Заметим, что $\vec{AD} = \vec{AC} + \vec{CD}$. Подставим это в формулу:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot (\vec{AC} + \vec{CD})|$</p><p>Используя свойство дистрибутивности скалярного произведения, получаем:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{AC} + (\vec{AB} \times \vec{AC}) \cdot \vec{CD}|$</p><p>Смешанное произведение $(\vec{AB} \times \vec{AC}) \cdot \vec{AC}$ равно нулю, так как векторное произведение $(\vec{AB} \times \vec{AC})$ перпендикулярно вектору $\vec{AC}$, а скалярное произведение перпендикулярных векторов равно нулю. Таким образом, формула для объёма упрощается:</p><p>$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{CD}|$</p><p>Используя циклическую перестановку векторов в смешанном произведении, которая не меняет его модуля, получим:</p><p>$V = \frac{1}{6} |(\vec{AC} \times \vec{CD}) \cdot \vec{AB}|$</p><p>Теперь рассмотрим геометрический смысл этого выражения.Пусть $a = |\vec{AB}|$ и $b = |\vec{CD}|$ — длины отрезков $AB$ и $CD$. По условию задачи, эти длины постоянны.Пусть $\alpha$ — угол между скрещивающимися прямыми $l_1$ и $l_2$. Так как прямые зафиксированы, угол $\alpha$ является постоянной величиной. Этот угол равен углу между векторами $\vec{AB}$ и $\vec{CD}$.Пусть $d$ — расстояние между прямыми $l_1$ и $l_2$. Это расстояние также является постоянным.</p><p>Смешанное произведение $|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}|$ можно интерпретировать как объём параллелепипеда, построенного на векторах $\vec{AB}$, $\vec{CD}$ и $\vec{AC}$.Величина векторного произведения $|\vec{AB} \times \vec{CD}|$ равна $a \cdot b \cdot \sin\alpha$. Вектор $\vec{n} = \vec{AB} \times \vec{CD}$ перпендикулярен обеим прямым $l_1$ и $l_2$.</p><p>Тогда $|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}| = | \vec{n} \cdot \vec{AC} |$. Скалярное произведение $\vec{n} \cdot \vec{AC}$ представляет собой произведение модуля вектора $\vec{n}$ на проекцию вектора $\vec{AC}$ на направление вектора $\vec{n}$. Проекция вектора $\vec{AC}$ (соединяющего точку на $l_1$ с точкой на $l_2$) на направление, перпендикулярное обеим прямым, как раз и является расстоянием $d$ между этими прямыми.</p><p>Таким образом:</p><p>$|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}| = |\vec{AB} \times \vec{CD}| \cdot d = (a \cdot b \cdot \sin\alpha) \cdot d$</p><p>Подставляя это в формулу для объёма, получаем:</p><p>$V = \frac{1}{6} a \cdot b \cdot d \cdot \sin\alpha$</p><p>Проанализируем полученную формулу в контексте задачи:</p><ul><li>$a = |AB|$ — длина отрезка $AB$, которая по условию постоянна.</li> <li>$b = |CD|$ — длина отрезка $CD$, которая по условию постоянна.</li> <li>$l_1$ и $l_2$ — фиксированные скрещивающиеся прямые, поэтому расстояние $d$ между ними постоянно.</li> <li>Угол $\alpha$ между фиксированными прямыми $l_1$ и $l_2$ также постоянен.</li></ul><p>Поскольку все величины в правой части формулы ($a, b, d, \alpha$) являются константами, объём тетраэдра $V$ также является постоянной величиной и не зависит от положения отрезков $AB$ и $CD$ на своих прямых.</p><p>Что и требовалось доказать.</p><p><b>Ответ:</b> Объём тетраэдра $ABCD$ не изменяется, так как он зависит только от длин отрезков $AB$ и $CD$, а также от расстояния и угла между скрещивающимися прямыми, на которых они лежат. Все эти величины в условиях задачи постоянны.</p>"
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№784 (с. 191)
Условие. №784 (с. 191)
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 191, номер 784, Условие

784. Отрезки AB и CD перемещаются по скрещивающимся прямым. Докажите, что объём тетраэдра ABCD при этом не изменяется.

Решение 2. №784 (с. 191)
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 191, номер 784, Решение 2
Решение 3. №784 (с. 191)
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 191, номер 784, Решение 3
Решение 6. №784 (с. 191)

Для решения этой задачи воспользуемся формулой для вычисления объёма тетраэдра через длины двух его скрещивающихся рёбер, расстояние между ними и угол между ними.

Пусть отрезки $AB$ и $CD$ лежат на скрещивающихся прямых $l_1$ и $l_2$ соответственно. Объём тетраэдра $ABCD$ можно выразить через векторы его рёбер. Стандартная формула для объёма через смешанное произведение векторов, выходящих из одной вершины (например, $A$), имеет вид:

$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{AD}|$

Преобразуем это выражение, чтобы использовать векторы скрещивающихся рёбер $\vec{AB}$ и $\vec{CD}$. Заметим, что $\vec{AD} = \vec{AC} + \vec{CD}$. Подставим это в формулу:

$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot (\vec{AC} + \vec{CD})|$

Используя свойство дистрибутивности скалярного произведения, получаем:

$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{AC} + (\vec{AB} \times \vec{AC}) \cdot \vec{CD}|$

Смешанное произведение $(\vec{AB} \times \vec{AC}) \cdot \vec{AC}$ равно нулю, так как векторное произведение $(\vec{AB} \times \vec{AC})$ перпендикулярно вектору $\vec{AC}$, а скалярное произведение перпендикулярных векторов равно нулю. Таким образом, формула для объёма упрощается:

$V = \frac{1}{6} |(\vec{AB} \times \vec{AC}) \cdot \vec{CD}|$

Используя циклическую перестановку векторов в смешанном произведении, которая не меняет его модуля, получим:

$V = \frac{1}{6} |(\vec{AC} \times \vec{CD}) \cdot \vec{AB}|$

Теперь рассмотрим геометрический смысл этого выражения.Пусть $a = |\vec{AB}|$ и $b = |\vec{CD}|$ — длины отрезков $AB$ и $CD$. По условию задачи, эти длины постоянны.Пусть $\alpha$ — угол между скрещивающимися прямыми $l_1$ и $l_2$. Так как прямые зафиксированы, угол $\alpha$ является постоянной величиной. Этот угол равен углу между векторами $\vec{AB}$ и $\vec{CD}$.Пусть $d$ — расстояние между прямыми $l_1$ и $l_2$. Это расстояние также является постоянным.

Смешанное произведение $|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}|$ можно интерпретировать как объём параллелепипеда, построенного на векторах $\vec{AB}$, $\vec{CD}$ и $\vec{AC}$.Величина векторного произведения $|\vec{AB} \times \vec{CD}|$ равна $a \cdot b \cdot \sin\alpha$. Вектор $\vec{n} = \vec{AB} \times \vec{CD}$ перпендикулярен обеим прямым $l_1$ и $l_2$.

Тогда $|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}| = | \vec{n} \cdot \vec{AC} |$. Скалярное произведение $\vec{n} \cdot \vec{AC}$ представляет собой произведение модуля вектора $\vec{n}$ на проекцию вектора $\vec{AC}$ на направление вектора $\vec{n}$. Проекция вектора $\vec{AC}$ (соединяющего точку на $l_1$ с точкой на $l_2$) на направление, перпендикулярное обеим прямым, как раз и является расстоянием $d$ между этими прямыми.

Таким образом:

$|(\vec{AB} \times \vec{CD}) \cdot \vec{AC}| = |\vec{AB} \times \vec{CD}| \cdot d = (a \cdot b \cdot \sin\alpha) \cdot d$

Подставляя это в формулу для объёма, получаем:

$V = \frac{1}{6} a \cdot b \cdot d \cdot \sin\alpha$

Проанализируем полученную формулу в контексте задачи:

  • $a = |AB|$ — длина отрезка $AB$, которая по условию постоянна.
  • $b = |CD|$ — длина отрезка $CD$, которая по условию постоянна.
  • $l_1$ и $l_2$ — фиксированные скрещивающиеся прямые, поэтому расстояние $d$ между ними постоянно.
  • Угол $\alpha$ между фиксированными прямыми $l_1$ и $l_2$ также постоянен.

Поскольку все величины в правой части формулы ($a, b, d, \alpha$) являются константами, объём тетраэдра $V$ также является постоянной величиной и не зависит от положения отрезков $AB$ и $CD$ на своих прямых.

Что и требовалось доказать.

Ответ: Объём тетраэдра $ABCD$ не изменяется, так как он зависит только от длин отрезков $AB$ и $CD$, а также от расстояния и угла между скрещивающимися прямыми, на которых они лежат. Все эти величины в условиях задачи постоянны.

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