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Homework Help: Can't integrate the e s here

  1. Sep 4, 2010 #1
    Can't integrate the "e"s here

    1. The problem statement, all variables and given/known data
    [tex]\int 2/e3x(6+e-3x)dx[/tex]

    2. Relevant equations
    I have no idea as to what equations to use, other than [tex]\int[/tex] e[tex]u[/tex] du = e [tex]u[/tex] + C

    3. The attempt at a solution
    [tex]\int[/tex] 2/(6e3x +1) dx
    u = 6e3x +1
    du = 18e3x dx

    and that's as far as I can get, I can't think of what else to do. HELP!!

    Thanks in advance.
  2. jcsd
  3. Sep 4, 2010 #2
    Re: Can't integrate the "e"s here

    please fix your latex code to make it readable
  4. Sep 4, 2010 #3


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    Homework Helper

    Re: Can't integrate the "e"s here

    Is it supposed to be this?
    [tex]\int \frac{2}{e^{3x}} (6 + e^{-3x}) dx[/tex]

    Or this?
    [tex]\int \frac{2}{e^{3x} (6 + e^{-3x})} dx[/tex]

    If it's the second, then I wouldn't distribute the e^(3x) at all. I would move it to the numerator, and then use substitution: u = (6 + e^(-3x)). Try it and see what happens.
    Last edited by a moderator: Sep 15, 2010
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