Question

Помогите решить, пожалуйста.
$1-tg(-\alpha )/sin \alpha +cos (-\alpha )$

Answer 1

$\frac{1-tg(-\alpha) }{Sin\alpha+Cos(-\alpha)} =\frac{1+tg\alpha }{Sin\alpha+Cos\alpha}=\frac{1+\frac{Sin\alpha }{Cos\alpha}}{Sin\alpha+Cos\alpha}}=\frac{\frac{Sin\alpha+Cos\alpha}{Cos\alpha} }{Sin\alpha+Cos\alpha} =\\\\=\frac{Sin\alpha+Cos\alpha}{Cos\alpha(Sin\alpha+Cos\alpha)}=\boxed{\frac{1}{Cos\alpha}}$