Предмет: Геометрия, автор: Fedor11

в треугольнике ABC(прямоугольный) угол C= 90 градусов, sinB=1/2. Найдите cosA

Ответы

Автор ответа: Аноним

sin 1/2 = 30градусов, значит угол B=30, а угол А=60градусов(сумма углов=180). Cos 60=1/2.

Ответ: 1/2

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