I have a few questions that I need help with for my precal class in college. The following have to prove the trigonometric identities: cos^{4}x + 2cos^{2}x sin^{2}x + sin^{4}x = 1 sin^{4}x - cos^{4}x = 1 - 2cos^{2}x thanks you, Mandy

Here's a hint that's good for both of those questions:

Try factoring them and then using the identity cos^{2}x + sin^{2}x = 1.

Hope this helps! Stephen La Rocque>