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Homework Help: Electric Field of Coaxial Cable

  1. May 10, 2009 #1
    http://img154.imageshack.us/img154/165/integrallll.jpg [Broken]

    After working it out myself, I have the logarithim part equal to:

    [ln b - lna] + [ln c - ln b] = [ln b/a + ln c/b] = ln c/a (Not sure about this statement!)

    I don't understand where the c^2 and ab came from with this integral?

    Any help?

    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. May 10, 2009 #2


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    Homework Helper
    Gold Member

    Take a careful look at the factors in front of each logarithm (they are different by a factor of 2) and remember that [itex]p\ln(x)=\ln(x^p)[/itex]
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