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Homework Help: Integration problem with e (check my work)

  1. Feb 14, 2007 #1
    1. The problem statement, all variables and given/known data

    (integrate)5e^(5x)*sin(e^(5x))dx

    2. Relevant equations



    3. The attempt at a solution

    I factored 5 out of the integration and made u to be e^5x, and du to be 5e^5x, or (1/5)du=e^(5x)dx. Because of this, the 5 factored out of the equation canceled out with the (1/5), leaving (integrate)u*sin(u).

    I integrated that, making sin(u)-u*cos(u) (I think) and pu the e^(5x)s back where the u's were. Am I right in doing this?
     
  2. jcsd
  3. Feb 15, 2007 #2
    [tex] \int{f'(x)\sin{f(x)} dx = -cos(f(x)) + C [/tex]
     
    Last edited: Feb 15, 2007
  4. Feb 15, 2007 #3
    Never mind. I figured it out like right after I posted. Sorry.
     
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