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    Integrate: 16sin^4(x)cos^4(x)

    I think i can integrate it. But i dont know how to start/ how to simplify the sin^4(x)cos^4(x) into something simple which i can integrate. Any help appreciated!
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    (Original post by Nirm)
    Integrate: 16sin^4(x)cos^4(x)

    I think i can integrate it. But i dont know how to start/ how to simplify the sin^4(x)cos^4(x) into something simple which i can integrate.
    think of the identity for sin2A=2sinAcosA
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    (Original post by TeeEm)
    think of the identity for sin2A=2sinAcosA
    All i can think of is (sin2A)^4 but that doesnt seem right because the answer is meant to be 3x/8 - sin4x/8 +sin8x/64 (+C). I am going to give it a go and see if i get anywhere. Thanks for the hint
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    (Original post by Nirm)
    All i can think of is (sin2A)^4 but that doesnt seem right because the answer is meant to be 3x/8 - sin4x/8 +sin8x/64 (+C). I am going to give it a go and see if i get anywhere. Thanks for the hint
    next consider sin2A =1/2 - 1/2cos(2A)
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    (Original post by Nirm)
    All i can think of is (sin2A)^4 but that doesnt seem right because the answer is meant to be 3x/8 - sin4x/8 +sin8x/64 (+C). I am going to give it a go and see if i get anywhere. Thanks for the hint
    Think you probably wanted to gothe other way and write your things in terms of cos2x instead
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    (Original post by TenOfThem)
    Think you probably wanted to gothe other way and write your things in terms of cos2x instead
    Yeah i did i guess
    (Original post by TeeEm)
    next consider sin2A =1/2 - 1/2cos(2A)
    This question is quiet long, still trying to complete it. I think i am on the right path
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    (Original post by Nirm)
    Yeah i did i guess

    This question is quiet long, still trying to complete it. I think i am on the right path
    hope it works
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    (Original post by TeeEm)
    hope it works
    Thank you! (too many things to multiply out and simplify but its looking so far)
 
 
 
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