How do you verify sec4xtan4x=sec2x+tan2x?

1 Answer
Sep 13, 2016

Prove trig expression

Explanation:

Transform the left side of the expression:
LS=sec4xtan4x=(sec2xtan2x)(sec2x+tan2x).
Since the first factor,
(sec2xtan2x)=(1cos2xsin2xcos2x)=
=1sin2xcos2x=cos2xcos2x=1
There for, the left side becomes;
LS=(sec2x+tan2x), and it equals the right side.