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Math Help - Intergrating Exponential Functions

  1. #1
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    Intergrating Exponential Functions

    How do you evaluate this:
    INT[e^(sin*pi*x) cos*(pi)x dx]

    do I let u=sin(pi)x so du/(cos(pi)x)=dx

    then, I plug in the values but I got a differernt answer from the book...can someone please help?
    Last edited by got_jane; February 7th 2008 at 06:19 PM.
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  2. #2
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    Krizalid's Avatar
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    Quote Originally Posted by got_jane View Post
    do I let u=sin(pi)x so du/(cos(pi)x)=dx
    The problem is that you're not applyin' the chain rule here.

    (See my signature for LaTeX typesetting.)
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  3. #3
    GAMMA Mathematics
    colby2152's Avatar
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    Quote Originally Posted by got_jane View Post
    How do you evaluate this:
    INT[e^(sin*pi*x) cos*(pi)x dx]

    do I let u=sin(pi)x so du/(cos(pi)x)=dx

    then, I plug in the values but I got a differernt answer from the book...can someone please help?
    u=sin(\pi x)
    du=\pi cos(\pi x) dx

    That should help...
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