Question

Prove:

sin^4x – cos^4x = sin^2x – cos^2x

Answer 1

\[\sin(4x) - \cos(4x) = \sin^2(x) - \cos^2(x)\]?

Answer 2

right

Answer 3

Shouldn't it be \(\sin^4(x) - \cos^4(x) = \sin^2(x) - \cos^2(x)\)?

Answer 4

Oh. OK

Answer 5

\[\sin^4(x) - \cos^4(x) = (\sin^2(x))^2 - (\cos^2(x))^2\]Right?

Answer 6

Hello...

Answer 7

@ParthKohli yes, that's an identity...

Answer 8

@isuckatmath9999 Ping

Answer 9

sorry i passed out =/

Answer 10

Hi again

Answer 11

So \(\sin^4 (x) - \cos^4(x) = (\sin^2(x))^2 - (\cos^2(x))^2\), correct?

Answer 12

why did you add on random exponents?

Answer 13

Because I can.

Answer 14

And it'd make my work easier...

Answer 15

but then it wouldn't help me

Answer 16

It would. Have patience :-)

Answer 17

I'm on a time schedule. I don't have time to be patient I'm like 8 assignments behind >.>

Answer 18

and apparently I can only do like 3 per day. So i'm fudged.

Answer 19

But do you agree with that statement there?