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vericacnae · Mar 8, 2012, 09:08 PM

^2 means to (second power)
I would really love to know exactly how to do it I'm completely confused

vericacnae · Mar 8, 2012, 09:09 PM

The directions say verify each identity

ebaines · Mar 9, 2012, 07:02 AM

Remember that tan(x) = sin(x)/cos(x), so if you make that substitution you get:

$<br /> \cos^2x + ( \frac {\sin^2x}{\cos^2x} ) \cos^2x = \cos^2x + \sin^2x<br />$

Now you apply the basic identity

$<br /> \cos^2x + \sin^2x = 1<br />$

In general for proving trig identities like this you should always replace any tangent, cortangent, secant and cosecant functions with their sine and cosine equivalents, and if you remember a few key identites it is usually pretty straight forward to work out.

Stratmando · Mar 10, 2012, 05:10 AM

ebaines is exceptional at math among other things, will help greatly.
I googled your formula and found this, seems helpful:
Trigonometric Identities