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Homework Help: Finding the derivative

  1. Nov 13, 2011 #1
    1. The problem statement, all variables and given/known data
    f(x)=(x2-x)(sin(x))


    2. Relevant equations
    Chain rule
    Product rule


    3. The attempt at a solution
    f'g(x)*g'(x)
    cosx

    (2x-x)(cosx)

    Would you use the product rule after using the power rule and chain rule?
     
  2. jcsd
  3. Nov 13, 2011 #2

    SammyS

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    Review the product rule !
     
  4. Nov 13, 2011 #3

    Mark44

    Staff: Mentor

    ???
    This looks like you're attempting to use the chain rule.
    No. Use the product rule first. You don't need the chain rule at all.
     
  5. Nov 13, 2011 #4
    (x2-x)cosx+sinx(2x-1)

    X2cosx-xcosx+2xsinx-sinx
     
  6. Nov 13, 2011 #5

    eumyang

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    That's more like it!
     
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