Question

ctg(3p/2+a) tg(p/2-a) -cos(p-a) sin(p/2) -a)

Answer 1

По формулам приведения

сtg(3π/2+α) tg(π/2-α) -cos(π-α) sin(π/2 -α)=-tgα*ctgα-(-cosα)*cosα=

-1+cos²α=-(1-cos²α)=-sin²α