(ii) Prove `cos x cos (60 -x) cos(60+x) = 1/4 cos 3x`

(ii) Prove cos x cos(60-x)cos(60+x)=(1)/(4)cos3x

Prove that : cos Acos(60-A)cos(60+A)=1/4cos3A

Prove that :cos A cos(60-A)cos(60+A)=(1)/(4)cos3A

Prove that: cos Acos(60^0-A)cos(60^0+A)=1/4cos3A

Prove that cos 3x=4 cos ^3x-3cos x

Period of cos x cos(60^(@) - x) cos (60^(@) + x) is

Prove that: (i) cos A cos(60^(@)-A)cos (60^(@)+A)=(1)/(4)cos 3A (ii) "tan" A+"tan"(60^(@)+A)-"tan"(60^(@)-A)=3 tan 3A .

Prove : int sin x cos 2 x cos 3 x dx = - 1/4 ((cos 2x)/2 - (cos 4x)/4 + (cos 6x)/6) + c

Prove : cos3x=4cos^(3)x-3cosx

If cos x cos 2x cos 3x=1//4 , then x=