Question

prove that sec^4 theta - sec^2 theta = tan^4 theta + tan^2 theta

Answer 1

let theta = a
Lhs= sec4a-sec2a

=sec2a(sec2a-1)
=tan2a+1(tan2a)
=tan4a+ tan2a
=Rhs
hence proved.

Answer 2

hope it may helps you