Question

Prove that:- (sin^4A)+(cos^4A) / 1-2sin^2Acos^2A = 1

Answer 1

sin^4A)+(cos^4A)
=( sin^2A)^2+(cos^2A)^2
= (sin^2A + cos ^ 2 A )^2 - 2 sin^2 A cos ^2 A
(beacuse a plus b whole square is equal to a sqare plus b sqare plus 2 ab)
= 1-2sin^2Acos^2A
hence proove it