Verify the identity: sec^2x tan^2x+sec^2x=sec^4x

Question

 This is for my Pre Calculus class. 

Answer 1

Make a list of the Pythagorean Identities:

 

sec²x · tan²x + sec²x = sec⁴x

sec²x (tan²x + 1) = sec²x

sec²x (sec² x) = sec⁴x

sec⁴ x= sec⁴ x