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

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

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

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

Find the value of (sin^4theta+cos^4theta)/(1-2sin^2 thetacos ^2 theta)

Show : 1 - Sin^4theta = Cos^2theta ( 1 + Sin^2theta )

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

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

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

Prove the following identities: 2(sin^(6)theta+cos^(6)theta)-3(sin^(4)theta+cos^(4)theta)+1=0sin^(6)theta+cos^(6)theta+3sin^(2)theta cos^(2)theta=1(sin^(8)theta-cos^(8)theta)=(sin^(2)theta-cos^(2)theta)(1-2sin^(2)theta cos^(2)theta)

The value of theta , lying between theta =0 and theta=(pi)/(2) and satisfying the equation . |{:(1+ cos^(2 ) theta , sin^(2) theta , 4 sin 4 theta ),(cos^(2) theta , 1+sin^2 theta , 4 sin 4 theta ),(cos^(2) theta , sin^(2) theta , 1+ 4 sin 4 theta ):}|=0 , is