Sin (x+210)+sin(x-210)=1/2√3

jawab

sin(x+210) + sin(x- 210)= 1/2 √3
2 sin 1/2 (2x)  cos 1/2 (420) = 1/2 √3
2 sin x cos 120 = 1/2 √3
2 (sin x)  (-1/2) = 1/2 √3
- sin x = 1/2 √3
sin x = - 1/2 √3

sin = -1/2 √3= - sin 60
x = (360 -60)= 300
x = (180 -(-60))= 240