Question

Simplificar a expressão:
sen(-x). cos(π/2 +x)/ tg(2π-x).cos(π-x)

Answer 1

$\frac{sen(-x). cos(\frac{\pi}{2} +x)}{ tg(2π-x).cos(π-x)} \\ \\ \frac{-sen(x).(-sin(x)}{ -tan(x).(-cos(x)} \\ \\ \frac{sen^2(x)}{sen(x)}=\boxed{sen(x)}$