Question

помогите решить пример.

Answer 1

$\frac{ \frac{Cos \alpha }{Sin \alpha }- \frac{Sin \alpha }{Cos \alpha } }{ \frac{Sin \alpha }{Cos \alpha }+ \frac{Cos \alpha }{Sin \alpha } } * \frac{3}{Cos2 \alpha }= \frac{ \frac{Cos ^{2} \alpha -Sin ^{2} \alpha }{Sin \alpha Cos \alpha } }{ \frac{Sin ^{2} \alpha +Cos ^{2} \alpha }{Sin \alpha Cos \alpha } } * \frac{3}{Cos2 \alpha } = \frac{Cos2 \alpha }{1}* \frac{3}{Cos2 \alpha } =3$