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Help with differentiating watch

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    I'm trying to differentiate
    3cos⁴xsin²x -3sin⁴xcos²x

    I've simplified it to 3sin²xcos²x(1-2sin²x)

    I've tried differentiating and ended up with a long mess.
    I got 6cos³xsinx-6sin³xcosx-12cos³xsin³x+12sin^5cosx-4cos³xsin³x

    I don't know if that's right and needs simplifying or if it's just wrong.

    Can someone give a step by step on how to differentiate it correctly?
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    Any angle formulae that might help with 1-2sin^2{x}?
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    (Original post by marmbite)
    I'm trying to differentiate
    3cos⁴xsin²x -3sin⁴xcos²x

    I've simplified it to 3sin²xcos²x(1-2sin²x)

    I've tried differentiating and ended up with a long mess.
    I got 6cos³xsinx-6sin³xcosx-12cos³xsin³x+12sin^5cosx-4cos³xsin³x

    I don't know if that's right and needs simplifying or if it's just wrong.

    Can someone give a step by step on how to differentiate it correctly?
    3\sin^2x \cos^2x(1-2\sin^2x)=3(\sin x \cos x)^2(1-2\sin^2x)

    Double angle formulae can be applied on \sin x \cos x and 1-2\sin^2x
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    (Original post by RDKGames)
    3\sin^2x \cos^2x(1-2\sin^2x)=3(\sin x \cos x)^2(1-2\sin^2x)

    Double angle formulae can be applied on \sin x \cos x and 1-2\sin^2x
    Oh I didn't even spot the possible double angle formulae use on the sin{x}cos{x} :facepalm:
 
 
 
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