Question

Даю 25 БАЛЛОВ ПОМОГИТЕ

Answer 1

$\frac{Sin(\frac{3\pi }{2}-\alpha)}{tg(\pi+\alpha)}*\frac{Ctg(\frac{\pi }{2}+\alpha)}{tg(\alpha-\frac{3\pi }{2})} =\frac{-Cos\alpha }{tg\alpha}* \frac{-tg\alpha }{-Ctg\alpha}=-\frac{Cos\alpha}{Ctg\alpha}=-\frac{Cos\alpha }{\frac{Cos\alpha}{Sin\alpha}}=\\\\=-\frac{Cos\alpha*Sin\alpha}{Cos\alpha} ==-Sin\alpha\\\\-Sin\alpha =-Sin\alpha$

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