sin(3x+p/3)=sin(x-p/6)

Question

sin(3x+p/3)=sin(x-p/6)

Answer 1

4cos^3x-3cosx=0
cosx(4cos^2x-3)=0
cosx=0
cos^2x=3/4
-11p/6
-3p/2
-7p/6