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Homework Help: Integration help

  1. Jul 10, 2011 #1
    [itex]\int[/itex] [itex]\frac{e^{\sqrt{x}}}{\sqrt{x}}[/itex]

    It's in the substitution rule/symmetric function section of my book, so I figure I probably have to use one of those techniques to solve it. I've tried doing a bunch of different u substitutions [itex]\sqrt{x}[/itex], [itex]e^{{\sqrt{x}}}[/itex], etc, but none of them seem right.

    How can you tell if a function is symmetric by looking at the equation? And whether it is even or odd?

    PS - couldn't figure out how to do it, but it's actually a definite integral that goes from 1 to 4. Also, if the top of the fraction is hard to read, it's [itex]e^{{\sqrt{x}}}[/itex].
  2. jcsd
  3. Jul 10, 2011 #2
    Try [tex]u = \sqrt{x}[/tex] again.
  4. Jul 10, 2011 #3
    Well now I feel a bit ridiculous. But I end up with [itex]/int[/itex]e^u * u^-2. Is there a way to solve this without integration by parts? We haven't gotten to it yet so I feel like there should be a way.

    Sorry for the lack of formatting, typing on my phone and I can't remember most of the tags.
  5. Jul 10, 2011 #4


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    If [itex]u = \sqrt{x}\,,[/itex] then what is du ?

    BTW: It's important to have the dx in the integral: [itex]\displaystyle \int\frac{e^{\sqrt{x}}}{\sqrt{x}} dx\,.[/itex]
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