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Homework Help: Evaluate the definite integral.

  1. Jan 29, 2012 #1
    1. The problem statement, all variables and given/known data

    Integrate from 0 to 1

    x47e-x48

    2. Relevant equations



    3. The attempt at a solution

    u = -x48

    du = -48x47dx

    dx = du / -48x47


    ∫eu * du/-48

    -[itex]\frac{1}{48}[/itex] ∫ eu du

    -[itex]\frac{1}{48}[/itex] eu


    -[itex]\frac{1}{48}[/itex] e1 - ( -[itex]\frac{1}{48}[/itex] e0)


    -[itex]\frac{e}{48}[/itex] + [itex]\frac{1}{48}[/itex]


    [itex]\frac{1-e}{48}[/itex]



    What did I do wrong? Webassign marked this as incorrect but I redid it and got same answer.
     
  2. jcsd
  3. Jan 29, 2012 #2

    vela

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    When x=1, u=-1.
     
  4. Jan 29, 2012 #3

    Char. Limit

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    Here's your problem. e^(-(1)^(48)) = e^(-1), not e^1.
     
  5. Jan 29, 2012 #4
    I see what I did wrong now, thank you.
     
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