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

ODE question

  1. Jun 14, 2008 #1
    I am reviewing differential equations, going through H.S. Bear's book Diff Eq: Concise Course.
    The problem set for the variables separate section were pretty easy and straightforward except for this one, which I can't see how to arrive at the answer given in the book. I'm probably just missing something silly, so maybe another pair of eyes looking at it will clear it up.

    (1-y[tex]^{2}[/tex]) dx - xy dy = 0

    the solution given is (x[tex]^{2}[/tex])(1-y[tex]^{2}[/tex]) = c
  2. jcsd
  3. Jun 14, 2008 #2


    User Avatar
    Science Advisor
    Homework Helper

    Hi bryanosaurus! :smile:
    erm … dx/x = ydy/(1 - y²) … ? :smile:
  4. Jun 14, 2008 #3
    Okay I got it now, I was fudging a sign when getting rid of the natural logs.
    Thanks :)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook