Question

1-tg(-x)/sinx+cos(-x)решите пж

Answer 1

$\frac{1-tan(-x)}{sin(x)+cos(-x)} =\frac{1-\frac{sin(-x)}{cos(-x)} }{sin(x)+cos(x)} =\frac{\frac{cos(-x)-sin(-x)}{cos(-x)_} }{sin(x)+cos(-x)} =\frac{cos(x)-(-sin(x))}{cos(x)(sin(x)+cos(x))}=\\=\frac{cos(x)+sin(x)}{cos(x)(sin(x)+cos(x))} =\frac{1}{cos(x)} =sec(x)$