Номер 4, страница 266 - гдз по физике 9 класс учебник Грачев, Погожев

Физика, 9 класс Учебник, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, издательство Вентана-граф, Москва, 2012

Авторы: Грачев А. В., Погожев В. А., Боков П. Ю.

Тип: Учебник

Серия: алгоритм успеха

Издательство: Вентана-граф

Год издания: 2012 - 2026

Цвет обложки: синий изображено здание и радуга

ISBN: 978-5-360-07412-0

Глава 8. Оптика. Параграф 42. Построение изображения в зеркалах. Упражнения - номер 4, страница 266.

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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Вентана-граф"
                            "field_cases" => null
                            "field_translit" => "ventana-graf"
                          ]
                          #original: array:6 [
                            "id" => 5174
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Вентана-граф"
                            "field_cases" => null
                            "field_translit" => "ventana-graf"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1211
                      #items: array:3 [
                        0 => App\Models\Term {#1212
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4180
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Грачев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Александр"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4180
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Грачев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Александр"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        1 => App\Models\Term {#1213
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 5484
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Погожев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Александрович"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 5484
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Погожев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Александрович"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        2 => App\Models\Term {#1214
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 3888
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Боков"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Павел"
                            "field_patronymic" => "Юрьевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 3888
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Боков"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Павел"
                            "field_patronymic" => "Юрьевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1215
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1216
                      #items: array:1 [
                        0 => App\Models\Term {#1217
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #original: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1218
                      #items: array:1 [
                        0 => App\Models\Term {#1219
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1220
                      #items: array:1 [
                        0 => App\Models\Term {#1221
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 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"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1222
                      #items: array:1 [
                        0 => App\Models\Term {#1223
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:8 [
                            "id" => 4697
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "алгоритм успеха"
                            "field_cases" => null
                            "field_foreign_lang_series" => null
                            "field_transcription_eng" => null
                            "field_translit" => "algoritm uspekha"
                          ]
                          #original: array:8 [
                            "id" => 4697
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "алгоритм успеха"
                            "field_cases" => null
                            "field_foreign_lang_series" => null
                            "field_transcription_eng" => null
                            "field_translit" => "algoritm uspekha"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1224
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1225
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1226
                      #items: array:1 [
                        0 => App\Models\Term {#1227
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6706
                            "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"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #original: array:10 [
                            "id" => 6706
                            "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"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "2"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1228
                      #items: array:1 [
                        0 => App\Models\Term {#1229
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 6900
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "доработанное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "dorabotannoe"
                          ]
                          #original: array:6 [
                            "id" => 6900
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "доработанное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "dorabotannoe"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1230
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "изображено здание и радуга"
                    "field_publication_year" => "2012"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся общеобразовательных организаций"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "580"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-u/"
                    "field_isbn" => "978-5-360-07412-0"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
                        "alt" => ""
                        "width" => "2294"
                        "height" => "3039"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1231
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1232
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1233
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/grachev-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1234
                      #items: array:1 [
                        0 => App\Models\Term {#1235
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #original: array:50 [
                    "id" => 1202
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1206}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1207}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1209}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1211}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1215}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1216}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1218}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1220}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1222}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1224}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1225}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1226}
                    "field_publication_number" => "2"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1228}
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                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "изображено здание и радуга"
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                    "field_part" => ""
                    "field_part_writing" => ""
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                    "field_for_whom" => "Учебник для учащихся общеобразовательных организаций"
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                    "field_default_folder" => "/fizika_09/grachev-u/"
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                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
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                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
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                        "width" => "2294"
                        "height" => "3039"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1231}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1232}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1233}
                    "field_url" => "/9-klass/fizika/grachev-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1234}
                    "field_metatags_title" => null
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                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
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                    ]
                  ]
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #visible: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1236
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
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            "id" => 1437978
            "created_at" => "2026-04-10 13:58:26"
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            "field_display_title" => "Оптика"
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            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1237
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
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          #attributes: array:24 [
            "id" => 1437986
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Построение изображения в зеркалах"
            "field_branch_order" => "42"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1242
              #items: array:1 [
                0 => App\Models\Term {#1239
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
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                  #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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                  #attributeCastCache: []
                  #dateFormat: null
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "261"
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            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
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            "field_h1" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1241
              #items: array:1 [
                0 => App\Models\Book {#1204}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1240
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1437986
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Построение изображения в зеркалах"
            "field_branch_order" => "42"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1242}
            "field_page_start" => "261"
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            "field_branch_title_in_content" => "0"
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            "field_h1" => null
            "field_description_top" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1241}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1240}
          ]
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          +timestamps: true
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1243
          #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" => 1437988
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Упражнения"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1244
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "265"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1245
              #items: array:1 [
                0 => App\Models\Book {#1204}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1254
              #items: array:1 [
                0 => App\Models\Branch {#1253
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
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                  #perPage: 15
                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1437986
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Построение изображения в зеркалах"
                    "field_branch_order" => "42"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1255 …2}
                    "field_page_start" => "261"
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                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1256 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1257 …2}
                  ]
                  #original: array:24 [
                    "id" => 1437986
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Построение изображения в зеркалах"
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1255 …2}
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                    "field_h1" => null
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                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1256 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1257 …2}
                  ]
                  #changes: []
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                  #attributeCastCache: []
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                  #touches: []
                  +timestamps: true
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                  #hidden: []
                  #visible: []
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                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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          ]
          #original: array:24 [
            "id" => 1437988
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Упражнения"
            "field_branch_order" => null
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            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1244}
            "field_page_start" => "265"
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            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
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            "field_h1" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1245}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1254}
          ]
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          +timestamps: true
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          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1183
      #items: array:2 [
        0 => App\Models\Element {#1175
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
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          #withCount: []
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          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1705317
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1164
              #items: array:1 [
                0 => App\Models\Edition {#1173
                  #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" => 6112
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
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                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
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                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1168 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1169 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6112
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
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                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1171 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1168 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1169 …2}
                    "field_content_source" => null
                  ]
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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" => "1438439"
              "type" => "task"
            ]
            "text" => "<p><strong>*4.</strong> Определите минимальный вертикальный размер висящего на стене зеркала, стоя перед которым человек ростом 1,8 м может полностью увидеть своё изображение.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "4-1.jpg"
                "alt" => null
                "width" => "494"
                "height" => 105
                "path" => "/media/fizika_09/grachev-u/0-42upr/4-1.webp?ts=1759503195"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1705317
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1164}
            "task" => array:2 [
              "refs" => "1438439"
              "type" => "task"
            ]
            "text" => "<p><strong>*4.</strong> Определите минимальный вертикальный размер висящего на стене зеркала, стоя перед которым человек ростом 1,8 м может полностью увидеть своё изображение.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "4-1.jpg"
                "alt" => null
                "width" => "494"
                "height" => 105
                "path" => "/media/fizika_09/grachev-u/0-42upr/4-1.webp?ts=1759503195"
              ]
            ]
          ]
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          #touches: []
          +timestamps: true
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1166
          #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" => 1813001
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1158
              #items: array:1 [
                0 => App\Models\Edition {#1167
                  #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" => 6644
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1163 …2}
                    "field_content_type" => "free"
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                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1159 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1162 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1161 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6644
                    "created_at" => "2026-04-10 13:58:26"
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            "text" => "<p><strong>Дано:</strong></p><p>Рост человека $H = 1,8$ м</p><p><strong>Найти:</strong></p><p>Минимальный вертикальный размер зеркала $\text{L}$ - ?</p><p><strong>Решение:</strong></p><p>Для того чтобы человек мог видеть свое изображение в зеркале полностью, лучи света от его макушки и от его ступней должны отражаться от краев зеркала и попадать ему в глаза. Рассмотрим ход лучей, используя законы геометрической оптики.</p><p>Пусть рост человека равен $\text{H}$. Обозначим положение макушки как точку $\text{A}$, ступней — как точку $\text{B}$, а глаз — как точку $\text{E}$.</p><p><strong>1.</strong> Чтобы увидеть свою макушку (точка $\text{A}$), луч света, исходящий из точки $\text{A}$, должен отразиться от верхнего края зеркала (точка $\text{C}$) и попасть в глаз (точка $\text{E}$). Согласно закону отражения света, угол падения равен углу отражения. Из геометрии следует, что точка отражения $\text{C}$ будет лежать на высоте, которая является средним арифметическим высот точек $\text{A}$ и $\text{E}$.</p><p><strong>2.</strong> Чтобы увидеть свои ступни (точка $\text{B}$), луч света, исходящий из точки $\text{B}$, должен отразиться от нижнего края зеркала (точка $\text{D}$) и попасть в глаз (точка $\text{E}$). Аналогично, точка отражения $\text{D}$ будет лежать на высоте, которая является средним арифметическим высот точек $\text{B}$ и $\text{E}$.</p><p>Пусть высота уровня глаз от пола равна $h_E$. Тогда высота макушки от пола равна $\text{H}$, а высота ступней равна 0.</p><p>Высота верхнего края зеркала $h_C$ над полом будет:</p><p>$h_C = \frac{H + h_E}{2}$</p><p>Высота нижнего края зеркала $h_D$ над полом будет:</p><p>$h_D = \frac{0 + h_E}{2} = \frac{h_E}{2}$</p><p>Минимальный вертикальный размер зеркала $\text{L}$ равен разности высот его верхнего и нижнего краев:</p><p>$L = h_C - h_D = \frac{H + h_E}{2} - \frac{h_E}{2} = \frac{H + h_E - h_E}{2} = \frac{H}{2}$</p><p>Как видно из формулы, минимальный размер зеркала для обзора в полный рост равен половине роста человека и не зависит от расстояния до зеркала или от высоты расположения глаз.</p><p>Подставим данное значение роста человека:</p><p>$L = \frac{1,8 \text{ м}}{2} = 0,9 \text{ м}$</p><p><strong>Ответ:</strong> 0,9 м.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Рост человека $H = 1,8$ м</p><p><strong>Найти:</strong></p><p>Минимальный вертикальный размер зеркала $\text{L}$ - ?</p><p><strong>Решение:</strong></p><p>Для того чтобы человек мог видеть свое изображение в зеркале полностью, лучи света от его макушки и от его ступней должны отражаться от краев зеркала и попадать ему в глаза. Рассмотрим ход лучей, используя законы геометрической оптики.</p><p>Пусть рост человека равен $\text{H}$. Обозначим положение макушки как точку $\text{A}$, ступней — как точку $\text{B}$, а глаз — как точку $\text{E}$.</p><p><strong>1.</strong> Чтобы увидеть свою макушку (точка $\text{A}$), луч света, исходящий из точки $\text{A}$, должен отразиться от верхнего края зеркала (точка $\text{C}$) и попасть в глаз (точка $\text{E}$). Согласно закону отражения света, угол падения равен углу отражения. Из геометрии следует, что точка отражения $\text{C}$ будет лежать на высоте, которая является средним арифметическим высот точек $\text{A}$ и $\text{E}$.</p><p><strong>2.</strong> Чтобы увидеть свои ступни (точка $\text{B}$), луч света, исходящий из точки $\text{B}$, должен отразиться от нижнего края зеркала (точка $\text{D}$) и попасть в глаз (точка $\text{E}$). Аналогично, точка отражения $\text{D}$ будет лежать на высоте, которая является средним арифметическим высот точек $\text{B}$ и $\text{E}$.</p><p>Пусть высота уровня глаз от пола равна $h_E$. Тогда высота макушки от пола равна $\text{H}$, а высота ступней равна 0.</p><p>Высота верхнего края зеркала $h_C$ над полом будет:</p><p>$h_C = \frac{H + h_E}{2}$</p><p>Высота нижнего края зеркала $h_D$ над полом будет:</p><p>$h_D = \frac{0 + h_E}{2} = \frac{h_E}{2}$</p><p>Минимальный вертикальный размер зеркала $\text{L}$ равен разности высот его верхнего и нижнего краев:</p><p>$L = h_C - h_D = \frac{H + h_E}{2} - \frac{h_E}{2} = \frac{H + h_E - h_E}{2} = \frac{H}{2}$</p><p>Как видно из формулы, минимальный размер зеркала для обзора в полный рост равен половине роста человека и не зависит от расстояния до зеркала или от высоты расположения глаз.</p><p>Подставим данное значение роста человека:</p><p>$L = \frac{1,8 \text{ м}}{2} = 0,9 \text{ м}$</p><p><strong>Ответ:</strong> 0,9 м.</p>"
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№4 (с. 266)
Условие. №4 (с. 266)
скриншот условия
Физика, 9 класс Учебник, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, издательство Вентана-граф, Москва, 2012, страница 266, номер 4, Условие

*4. Определите минимальный вертикальный размер висящего на стене зеркала, стоя перед которым человек ростом 1,8 м может полностью увидеть своё изображение.

Решение. №4 (с. 266)

Дано:

Рост человека $H = 1,8$ м

Найти:

Минимальный вертикальный размер зеркала $\text{L}$ - ?

Решение:

Для того чтобы человек мог видеть свое изображение в зеркале полностью, лучи света от его макушки и от его ступней должны отражаться от краев зеркала и попадать ему в глаза. Рассмотрим ход лучей, используя законы геометрической оптики.

Пусть рост человека равен $\text{H}$. Обозначим положение макушки как точку $\text{A}$, ступней — как точку $\text{B}$, а глаз — как точку $\text{E}$.

1. Чтобы увидеть свою макушку (точка $\text{A}$), луч света, исходящий из точки $\text{A}$, должен отразиться от верхнего края зеркала (точка $\text{C}$) и попасть в глаз (точка $\text{E}$). Согласно закону отражения света, угол падения равен углу отражения. Из геометрии следует, что точка отражения $\text{C}$ будет лежать на высоте, которая является средним арифметическим высот точек $\text{A}$ и $\text{E}$.

2. Чтобы увидеть свои ступни (точка $\text{B}$), луч света, исходящий из точки $\text{B}$, должен отразиться от нижнего края зеркала (точка $\text{D}$) и попасть в глаз (точка $\text{E}$). Аналогично, точка отражения $\text{D}$ будет лежать на высоте, которая является средним арифметическим высот точек $\text{B}$ и $\text{E}$.

Пусть высота уровня глаз от пола равна $h_E$. Тогда высота макушки от пола равна $\text{H}$, а высота ступней равна 0.

Высота верхнего края зеркала $h_C$ над полом будет:

$h_C = \frac{H + h_E}{2}$

Высота нижнего края зеркала $h_D$ над полом будет:

$h_D = \frac{0 + h_E}{2} = \frac{h_E}{2}$

Минимальный вертикальный размер зеркала $\text{L}$ равен разности высот его верхнего и нижнего краев:

$L = h_C - h_D = \frac{H + h_E}{2} - \frac{h_E}{2} = \frac{H + h_E - h_E}{2} = \frac{H}{2}$

Как видно из формулы, минимальный размер зеркала для обзора в полный рост равен половине роста человека и не зависит от расстояния до зеркала или от высоты расположения глаз.

Подставим данное значение роста человека:

$L = \frac{1,8 \text{ м}}{2} = 0,9 \text{ м}$

Ответ: 0,9 м.

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