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Dealing with functions of several variables

  1. Jun 29, 2008 #1
    1. The problem statement, all variables and given/known data
    Assuming [itex]x > -1[/itex] and [itex]y > -1[/itex], find the following integral:
    [tex]\displaystyle \int_0^1 \frac{t^x - t^y}{\ln t} dt[/tex]

    2. Relevant equations

    3. The attempt at a solution
    I have no idea where to start on this one... It came up in an exam for a class dealing with functions of several variables (eg, f(x,y,z)) so I don't think it's a usual substitution problem...

    I tried writing it as [tex]\int t^x \ln(-t) dt[/tex] (minus the same for y) but I couldn't get any further...

    Do I perhaps have to find some taylor polynomial or something?
  2. jcsd
  3. Jun 29, 2008 #2
    Re: Integral

    This is wrong that's not the same integral ( do you know why?)

    Use IBP.
  4. Jun 29, 2008 #3
    Re: Integral

    Sorry I screwed up there, heh.

    Anyway, I just found out that this question in the exam was part of some chapter that is now omitted, that would explain why I have no idea how to start on this one ^^
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