Question

Verify the identity.
cos 4x + cos 2x = 2 - 2 sin^2 2x - 2 sin^2 x

Answer 1

What are you being axed 2 do?

Answer 2

Verify the identity

Answer 3

You can factor out a 2 from the right function first of all.
also, note that \[\sin^2(x) = \cos(x)-\]

Answer 4

\[\cos^2(x)-1\]

Answer 5

=2(1-1 cos^2-1 x - 1 cos^2-1x)

Answer 6

what should I do next?

Answer 7

Wait, what is ur function, I'm trying to see what you wrote, correct me if I'm wrong, but is this your function:
\[\cos(4x)+\cos(2x) = 2-2\sin^2(2x)-2\sin^2(x)\]

Answer 8

thats correct