Q7 of 62 Page 81

Prove that-

We know that-




Now,


L.H.S = sin 3x + sin 2x - sin x


= (sin 3x - sin x) + sin 2x



= 2 cos 2x sin x + 2 sin x cos x [∵ sin 2x = 2 sin x cos x]


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




= R.H.S


Hence, L.H.S = R.H.S…Proved


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