Question

O valor de k=cos(π+x)*sen(90°-x)*tag(π+x)/sen(π-x)*cos(2π-x)*cotg(90°+x) é ?

Answer 1

$\mathsf{\dfrac{cos(\pi+x)\cdot sen(90-x)\cdot tg(\pi+x)}{sen(\pi-x)\cdot cos(2\pi-x)\cdot cotg(90+x)}}$

$\mathsf{\dfrac{cos(\pi+x)\cdot sen(90-x)\cdot sen(\pi+x)\cdot sen(90+x)}{sen(\pi-x)\cdot cos(2\pi-x)\cdot cos(\pi+x)\cdot cos(90+x)}}$

$\mathsf{\dfrac{(-cosx)\cdot cosx\cdot(-senx)(cosx)}{senx\cdot cosx\cdot(-cosx)(-senx)}}$

$\mathsf{\dfrac{cosx}{senx}}$

$\boxed{\mathsf{cotgx}}$