Question

Помогите пожалуйстаааааа

Answer 1

$1)Cos^{2}\alpha*tg^{2}(-\alpha )-1=Cos^{2}\alpha*(-\frac{Sin^{2}\alpha}{Cos^{2}\alpha})-1=-Sin^{2}\alpha-1\\\\2)\frac{1+Sin\beta }{Cos\beta }*\frac{1-Sin\beta }{Cos\beta }=\frac{(1+Sin\beta)(1-Sin\beta)}{Cos\beta*Cos\beta}=\frac{1-Sin^{2}\beta}{Cos^{2}\beta}=\frac{Cos^{2}\beta}{Cos^{2}\beta}=1$