Question

Verify the identity.

cos 4x + cos 2x = 2 - 2 sin^2 2x - 2 sin^2 x

Answer 1

lack of something likes = or + or else. check the problem please

Answer 2

that's it actually it says nothing else

Answer 3

even between sin2x and 2x?

Answer 4

so what does sin 2 2x mean?

Answer 5

cos 4x + cos 2x = 2 - 2 sin^2 2x - 2 sin^2 x
there sorry! :)

Answer 6

ok. edit the question in case there is someone stop by and he has a good idea.I ll try

Answer 7

ok

Answer 8

break 2 = 1+1 . and you have 1- 2sin^2(2x) = cos4x and 1 -2sin^2 x = cos 2x . and you have it done. start from left side
hope this helps

Answer 9

sorry start from right side

Answer 10

cos 4x + cos 2x = 2-2 sin^2 x - 2 sin^2 x
cos 4x + cos 2x = 1-2 sin^2 x 1-2 sin^2 x
cos 4x + cos 2x = cos 4x + cos 2x ???

Answer 11

yes

Answer 12

Thank you! :)