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Homework Help: Help on derivatives!

  1. Oct 29, 2011 #1
    1. The problem statement, all variables and given/known data

    Let f(x) = sqrt(sin(e^(x^4*sinx)))

    Find f '(x)

    I tried this many times and it's really frustrating!

    I made it a composition function : f(g(h(x)))

    but I'm not getting the answer at all.

    At the end, I found :
    1/2(sin(e^((x^4)(sinx))))^(-1/2) (cos(e^(x^4 sinx))) (e^(x^4 sinx)) (4x^3 cosx)

    But it's wrong.

    Could someone please tell me where I went wrong or how to solve this please.
  2. jcsd
  3. Oct 29, 2011 #2


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    Homework Helper

    You left out the blue part.

  4. Oct 29, 2011 #3
    Could you please tell me how you got the blue part?

    I put it in and it's still wrong :(
  5. Oct 29, 2011 #4


    Staff: Mentor

    Product rule.
  6. Oct 29, 2011 #5


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    Homework Helper

    Sorry, I also was mistaken, the red part is wrong, as you have to apply the product rule on x4sinx.

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