If 3sinx + √ 3 cos x = 2 √ 3 sin (x + y), (- Pie)

If 3sinx + √ 3 cos x = 2 √ 3 sin (x + y), (- Pie)


3sinx+√3 cos x=2√3(√3/2 sin x+1/2cosx)=2√3 sin(x+π/6)=2√3 sin(x+y)
Y = π / 6 + 2K π, K belongs to integer, and because y belongs to (- π, π)
So y = π / 6