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

Question

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

Answer 1

  = 2*(-sina*cosa*-tga) / (-tga *sina)= -2 sin^2a  / (sin^2a/cosa)= 
=- 2cosa