sin 2x + 2sin 4x + sin 6x = 4cos² x sin 4x

Open in App

Solution

L.H.S. = sin 2x + 2 sin 4x + sin 6x

= [sin 2x + sin 6x] + 2 sin 4x

= 2 sin 4x cos (– 2x) + 2 sin 4x

= 2 sin 4x cos 2x + 2 sin 4x

= 2 sin 4x (cos 2x + 1)

= 2 sin 4x (2 cos² x – 1 + 1)

= 2 sin 4x (2 cos² x)

= 4cos² x sin 4x

= R.H.S.

Suggest Corrections

Similar questions

sin 2 x + 2 sin 4 x + sin 6 x = 4 {cos}^{2} x sin 4 x

s i n 2 x + 2 s i n 4 x + s i n 6 x = 4 c o s^{2} x s i n 4 x

sin x 2 x + 2 sin 4 x + s i n 6 x = 4 {cos}^{2} x . sin 4 x

sin 2 x - sin 4 x + sin 6 x = 0

sin 6 x = sin 4 x - sin 2 x

x

Join BYJU'S Learning Program