Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Need help with complex integral

  1. Sep 24, 2009 #1
    Hi,i would be gratefull if anyone could help me with this problem.

    [tex]\frac{2}{\pi}[/tex][tex]\int \frac{cos(ux)}{\sqrt{x}} dx[/tex]
    x goes from zero to infinity.

    thanks in advance.
  2. jcsd
  3. Sep 24, 2009 #2


    User Avatar
    Science Advisor
    Homework Helper

    Assuming you know a thing or two about Gaussian integrals, you could try substituting [itex]y^2 = x[/itex]...
  4. Sep 24, 2009 #3
    yes I tried that and I got[tex]\frac{\sqrt{2}}{\sqrt{u\pi}}[/tex]
    but correct is [tex]\frac{1}{\sqrt{u}}[/tex] .
    any other way of solving?
  5. Sep 24, 2009 #4


    User Avatar
    Science Advisor
    Homework Helper

    Are you sure 1/√u is correct? Maple and wolfram alpha agree with your answer.
  6. Sep 24, 2009 #5
    Ok my mistake,thank you all.Maple rules :smile:
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook