Предмет: Математика, автор: alecksolodov20

Радиус сферы равен 15 см. Найдите длину окружности сечения, удаленного от центра сферы на 12 см.
Помогите пожалуйста!!!!

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Автор ответа: banner5

169

Нужно найти радиус сечения. Найдем его через прямоугольный треугольник, где гипотенуза - радиус сферы, катет - высота - расстояние до сечения. По Т. Пифагора r=

\/225-144=9. Длина окружности равна 2пr=18п.

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