Предмет: Геометрия, автор: Gertseyn

Пожалуйста, срочно надо!
Плоскость пересекает сферу. Диаметр сферы, проведенный в одну из точек линии пересечения, имеет длину 4 корня из 2 и составляет с плоскостью угол в 45 градусов.
Найдите длину линии пересечения.

Ответы

Автор ответа: nafanya2014

Из треугольника АОК: АО=R; AK=r ( cм рисунок в приложении)

r=R·sin 45°=4√2·(√2/2)=4

C=2πr=2π·4=8π≈25,12

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