Precalc/Trig Help

<p>I can’t figure out where to start on some problems for extra credit in precalc. </p>

<p>For these you have to confirm each identity:</p>

<li><p>(sin^6x) + (cos^6x) = 1 - (3sin^2x)(cos^2x)</p></li>
<li><p>(cos^6x) - (sin^6x) = (cos^2x - sin^2x)(1 - cos^2x*sin^2x)</p></li>
</ol>

<p>You have to confirm these using hyperbolic trig functions:</p>

<li> cosh^2x - sinh^2x = 1</li>
</ol>

<p>Assume that A,B, and C are angles of triangle ABC. Prove the following identities:</p>

<p>a. sin(A + B) = sin C</p>

<p>If you any CC math geniuses can at least tell me where to start on some of these, I’d appreciate it. Trig isn’t my specialty. :D</p>