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Second order nonlinear differential equation

  1. Jan 15, 2009 #1
    i am facing problem in solving the following differential equation. help me.
    y''+ayy'+b=0, where y is a function of x, 'a' & 'b' are constants.

    i have tried substituting y'=u, which implies u'=u*dy/dx, these substitution change the equation to first order but i found no way ahead.
    Last edited: Jan 15, 2009
  2. jcsd
  3. Jan 15, 2009 #2


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    Homework Helper

    To do this, recognize that you can reverse the chain rule on the term yy' to get (y^2/2)'. You can then directly integrate the equation to get a first order equation. (Don't forget the arbitrary constant that comes from doing so).
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