Prove that, cosα cos(120+α) cos(240+α)= $\frac{1}{4}$ cos3α
Prove that, cosα cos(120+α) cos(240+α)= $\frac{1}{4}$ cos3α $cos\alpha cos(120 + \alpha )cos(240 + \alpha )$ = $\frac{1}{4}cos3\alpha$ Solution: cosα cos(120°+α) …
Prove that, cosα cos(120+α) cos(240+α)= $\frac{1}{4}$ cos3α $cos\alpha cos(120 + \alpha )cos(240 + \alpha )$ = $\frac{1}{4}cos3\alpha$ Solution: cosα cos(120°+α) …