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!

Homework Help: Partial differential equation

  1. Oct 26, 2005 #1
    Hi does anyone know how to solve this partial differential equation. My brain appears to be burping (and strangely my past notes don't seem to have any similar equation in):confused:
    [tex]\frac{\partial{\psi}}{\partial{x}} = k(x+y)[/tex]
    Anyone know any good tutorials or webpages for these sorts of equation? I'm a bit rusty with them
  2. jcsd
  3. Oct 26, 2005 #2
  4. Oct 26, 2005 #3


    User Avatar
    Science Advisor

    [tex]\frac{\partial{\psi}}{\partial{x}} = k(x+y)[/tex]

    Since x and y are independent, all you can do is integrate, with respect to x, treating y as a constant:
    [tex]\psi(x,y)= \frac{k}{2}x^2+ yx+ f(y)[/tex]
    Since the partial derivative wrt x is taken treating y as a constant, f(y) could be any function of y alone- its derivative will be 0.
  5. Oct 26, 2005 #4
    I tried that but didn't get the right answer, I'll give it another shot.

    Although isn't the second term kyx as it too is multiplied by k? Or am I being incredibly dense, it does happen a lot
  6. Oct 27, 2005 #5
    Turn out the reason I was going wrong wasn't my method, I lost a minus in the calculation (slippery little blighters):rolleyes:

    Thanks for the help anyway
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook