Hi all, I have a question proving an identity:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]sin(4x) = 4sin(x)cos^3(x)-4sin^3(x)cos(x)[/tex]

I can't seem to figure it out. I know I should be using the known identities:

[tex]sin(2x) = 2sin(x)cos(x)[/tex]

and probably:

[tex]cos(2x) = 1-2sin^2(x)[/tex]

but I'm stuck. Please help!

Thanks!

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# Verifying Identities.

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