Предмет: Алгебра, автор: voskanyan091

В треугольнике АВС угол С равен 90, АС=9, соsА =1/3. Найдите АВ

Ответы

Автор ответа: KuOV

Косинус острого угла прямоугольного треугольника равен отношению прилежащего катета к гипотенузе:

cos∠A = AC / AB

AB = AC / cos∠A

AB = 9 / (1/3) = 27

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