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Homework Help: Impossible integral

  1. Dec 9, 2007 #1
    ---> how do I solve this integral?

    integral from -1 to 1/(sqrt(3)) of e^(arctan y) over (1+y^2)...

    Am I supposed to use integration by parts or what?
     
  2. jcsd
  3. Dec 9, 2007 #2

    Avodyne

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    As a general rule, a good strategy to try is a substitution of the form u = ugliest subpiece. In this case, u = arctan y.
     
  4. Dec 9, 2007 #3
    i definitely cannot make out what your integral is

    you should really learn latek, lol. i learned latek around my 30th posting :p
     
  5. Dec 9, 2007 #4

    cristo

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    The integral is this: [tex]\int_{-1}^{1/\sqrt{3}}\frac{\exp(\arctan y)}{(1+y^2)}dy[/tex]

    frasifrasi; click on the image to see the latex code.
     
  6. Dec 9, 2007 #5
    so, a simple u sub will work? then I would have to sub back in before evaluating, correct?
     
  7. Dec 9, 2007 #6
    correct! or you could evaluate during your substitution which changes your intervals, but it's all up to you.
     
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