Question

use the trigonometric identities to answer the following :
5. 1-sin^2x=
6. sec^2x-1=

Answer 1

http://www.gradeamathhelp.com/image-files/trigonometric-identities-pythagorean.gif

what do you think?

Answer 2

or google

Answer 3

here's a fun trick: remember only this one. for life.
\[\sin^2 (x) + \cos^2(x) = 1\]
and if you divide everything by cos^2(x)
\[\frac{ \sin^2(x) }{ \cos^2(x) } + \frac{ \cos^2(x) }{ \cos^2(x) } = \frac{ 1 }{ \cos^2(x) }\]\[\tan^2(x) + 1 = \sec^2(x)\]

Answer 4

So now you can play around with these identities given to you by @jdoe0001 and @Euler271 to solve for the function you're looking for.