Question

упростите выражение
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Answer 1

$sin(\pi -\alpha )=sin\alpha \\\\cos(\frac{\pi }{2} -\alpha )=sin\alpha \\\\sin(\frac{3\pi }{2} -\alpha )=-cos\alpha$

$\frac{sin(\pi -\alpha )+cos(\frac{\pi }{2}-\alpha )}{sin(\frac{3\pi }{2} -\alpha )}=\frac{sin\alpha +sin\alpha }{-cos\alpha }= \frac{2sin\alpha }{-cos\alpha } =-2tg\alpha$