Question

what is sin^2-cos^2

Answer 1

\[\sin^2(x)+\cos^2(x)=1\]So if we subtract \(2\cos^2(x)\) from both sides,\[\sin^2(x)+\cos^2(x)-2\cos^2(x)=1-2\cos^2(x)\]Or,\[\sin^2(x)-\cos^2(x)=1-2\cos^2(x)\]

Answer 2

sin^2 x + cos^2 x = 1

This means sin^2 x = (1-cos^2 x)

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

Answer 3

With a little bit more work, you can find that \[1-2\cos^2(x)=-\cos(2x)\]

Answer 4

ok thank you

Answer 5

You're welcome.