Question

Упростите
1-tg(-a)/(cos(3п/2-а)-sin(a-3п/2))

Answer 1

$frac{1-tg(-a)}{cos(frac{3 pi }{2}-a)-sin(a-frac{3 pi }{2})}= frac{1+tga}{-sina-cosa}=-frac{1+tga}{sina+cosa}=-frac{1+ frac{sina}{cosa}}{sina+cosa}=-frac{cosa+sina}{(sina+cosa)*cosa}=-frac{cosa+sina}{(sina+cosa)*cosa}=-frac{1}{cosa}$