Question

sin alfa- sin (pi/3-alfa)

Answer 1

 $sin alpha -sin(frac{pi}{3}- alpha )=\\= 2sinfrac{ alpha -frac{pi}{3}+ alpha }{2}cdot cos{frac{ alpha +frac{pi}{3}- alpha }{2}=2sin( alpha -frac{pi}{6})cdot cosfrac{pi}{6}=sqrt3cdot cos( alpha -frac{pi}{6})$