Find the exact solutions of the equation in the interval [0, 2π).
sin 2x + sin x = 0
2 sin cos + sin = 0
sin(2cos +1) = 0 so sin = 0 (at 0 pi 2 pi) or cos = -1/2 ( at 2pi/3 4pi/3 )
+322 
+36915 
