Предмет: Геометрия, автор: greyndzher90

Найдите диагональ куба ABCDA1B1C1D1 и двугранный угол A1CDB, если ребро куба равно 5см.

Ответы

Автор ответа: emerald0101

0

$d^2=3a^2;d= sqrt{3}a= sqrt{3}*5=5sqrt{3};$
Линейный угол-это угол образованный пересечением двугранного угла с плоскостью, перпендикулярной к его ребру. Пло°скость ADD1перпендикулярна ребру CD двугранного угла A1CDB. Линейный угол двугранного угла A1CDB это угол ADA1, он равен 45°, т к A1D - диагональ квадрата.

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