Question

Proving trig equations

Answer 1

\(\sf cos~4x~+~cos~2x~=~2~-~2~sin^22x~-~2 sin^2 x\)

Answer 2

@hartnn

Answer 3

use the identity
\(\Large \cos 2A = 1-2\sin^2 A\)

Answer 4

for both
cos 4x
and cos 2x


for cos 4x, A =2x
for cos 2x , A= x

Answer 5

mk, so \(\sf 1-2sin^2 4x + 1-2sin^2 2xx = 2 − 2 sin^22x − 2sin^2x\)?

Answer 6

good! :)

Answer 7

Wait, so is that it?

Answer 8

yep, thats it! :)

Answer 9

@sleepyjess hi

Answer 10

@crazychickengirl123

Answer 11

@luckcoins888

Answer 12

Yes?

Answer 13

hi

Answer 14

nice to see u again

Answer 15

@crazychickengirl123

Answer 16

why are you spamming my question?

Answer 17

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