" (ii) "cos3 theta=4cos^(3)theta-3cos theta

Prove that : cos3 theta=4 cos^3 theta-3 cos theta .

Use Binomial theorem and De Moivre's theorem to show cos 3 theta=4 cos^3 theta-3cos theta , sin3theta=3sin theta-4 sin^3 theta Express cos ntheta as sum of product of power of sin theta "and" cos theta . Do the same thing for sin n theta.

cos 4theta = cos 3theta - cos2theta

(sin ^ (3) theta + sin3 theta) / (sin theta) + (cos ^ (3) theta-cos3 theta) / (cos theta) =

Prove that: sin4 theta=4 sin theta cos^(3)theta-4cos theta sin^(3)theta

Prove that: sin theta cos^(3)theta-cos theta sin^(3)theta=(1)/(4)sin4 theta

Prove that sin theta cos^(3)theta - cos theta sin^(3) theta = (1)/(4) sin 4 theta .

64cos^(3)theta sin^(4)theta=cos7 theta-cos5 theta-3cos3 theta+3cos theta

64cos^(3)theta sin^(4)theta=cos7 theta-cos5 theta-3cos3 theta+3cos theta

4 sin theta * cos^(3) theta-4 cos theta * sin ^(3)theta= A) 4 cos theta B) cos 4 theta C) 4 sin theta D) sin 4 theta