1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    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!

Use Cauchy Residue Theorem to find the integral

  1. Sep 4, 2012 #1
    1. The problem statement, all variables and given/known data

    To find the integral by Cauchy Residue Theorem and apply substitution method.

    2. Relevant equations

    To show: ∫[itex]^{2∏}_{0}[/itex][itex]\frac{cosθ}{13+12cosθ}[/itex]=-[itex]\frac{4∏}{15}[/itex]

    3. The attempt at a solution
    The solution I have done is attached. It is different as what the question wants me to show. I do not know where I did it wrong.

    Attached Files:

  2. jcsd
  3. Sep 4, 2012 #2
    Otherwise it looks fine to me, except that
    [tex] 6z^3+13z^2+6z = 6 z(z+2/3)(z+3/2) \neq z(z+2/3)(z+3/2) [/tex]
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook