I have a few questions that I need help with for my precal class in college. The following have to prove the trigonometric identities:

cos⁴x + 2cos²x sin²x + sin⁴x = 1

sin⁴x - cos⁴x = 1 - 2cos²x

thanks you,
Mandy

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

Try factoring them and then using the identity cos²x + sin²x = 1.

Hope this helps!
Stephen La Rocque>