Предмет: Геометрия, автор: vikyshka99

в треугольнике ABC угол C равен 90 градусов, COS A = корень из 15 деленое на 4. найдите COS B

Ответы

Автор ответа: Juliaair

0

cos180= -1(косинус суммы всех углов тр-ка).
cos90= 0.
0+кор.из15/4 +х= -1.
х= -1-кор.из15/4 = -4+кор.из15/4.
Ответ: -4+кор.из15/4.

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