Prove that `1-sin^(4)theta=cos^(2)theta(1+sin^(2)theta)`

Prove that : sin^(4)theta-cos^(4)theta=2sin^(2)theta-1

Prove that (sin^(4)theta-cos^(4)theta)/(sin^(2)theta-cos^(2)theta)=1

Prove that sin^(6)theta+cos^(6)theta=1-3sin^(2)theta cos^(2)theta

Prove that sin^(6)theta+cos^(6)theta=1-3sin^(2)theta.cos^(2)theta.

Prove that sin^(4)theta-cos^(4)theta=sin^(2)theta-cos^(2)theta

Prove that : cos^(4)theta - cos^(2)theta = sin^(4)theta - sin^(2) theta

Prove that sin^(2)theta+sin^(2)2 theta+sin^(2)3 theta+....+sin^(2)n theta=(n)/(2)-(sin n theta cos(n+1)theta)/(2sin theta)

Prove that: 1+cos^(2)2 theta=2(cos^(4)theta+sin^(4)theta)

Prove that sin^(4)theta+cos^(4)theta=1-(1)/(2)sin^(2)2 theta=(1)/(2)(1+cos^(2)2 theta)