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Homework Help: First order ODE solution

  1. Aug 19, 2010 #1
    1. The problem statement, all variables and given/known data
    Solve first order ODE

    2. Relevant equations


    3. The attempt at a solution
    Integrating factor
    [tex]p=\exp(-\int \frac{2}{x})=\exp(-2\ln x)=x^{-2}[/tex]

    Multiplying through by the integrating factor

    Integrating both sides

    Dividing through by [tex]x^{-2}[/tex]

    The problem comes when I use say, Maple to check the answer, it gives


    Any ideas? Thanks
  2. jcsd
  3. Aug 19, 2010 #2


    User Avatar
    Science Advisor

    No, the right hand side of your original equation was [itex]x^2+ 1[/itex]. Multiplying that by [itex]x^{-2}[/itex] gives [itex]1+ x^{-2}[/itex]. You've dropped the "1".

  4. Aug 19, 2010 #3
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