1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Please help with this integral.

  1. Mar 11, 2010 #1
    Can someone help me evaluate this integral?

    \int\limits_{-\infty}^{\infty} dz' \frac{1}{\sqrt{(x-x')^2 + (y-y')^2 + (z-z')^2}}

    Mathematica is telling me that this guy diverges. But it CAN'T! This is supposed to give me the reduced Green's function for two semi-infinite plates that meet at a right angle on the z-axis.
  2. jcsd
  3. Mar 11, 2010 #2


    User Avatar
    Science Advisor

    For large z' the integrand behaves like 1/|z'|, leading to divergence.
  4. Mar 11, 2010 #3
    It does indeed diverge.

    To solve you could use
    [tex]z-z'=\sqrt{(x-x')^2+(y-y')^2}\sinh t[/tex]
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook