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в цилиндр вписана правильная четырехугольная пирамида,боковая грань которой образует с плоскостью основания угол а .Высота пирамиды Н .Найдите площадь основания цилиндра.
Ответы 1
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SF/EF=tgαEF=SF/tgα=H/tgαпо теореме ПифагораAF²=EF²+EA²EF=EAAF=(√2H)/tgα=RS=πR²=(2πH²)/tg²α
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Автор:
beard - 5 лет назад
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