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Homework Help: The Devil's in the Algebra.

  1. Feb 22, 2004 #1
    I need to put this general solution to a differential in the following form:

    My solution is in the form (-x^3)(y^(-1)) + (x^2)y = C

    It needs to be in the form y = (x^(-2))[c+-((c^2) + x^5)^(1/2)]

    I've been noodling around with it for a while and it's not working out for me. Does anyone something I can factor out or multiply by that will put it into a friendlier form?

  2. jcsd
  3. Feb 22, 2004 #2


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    Science Advisor
    Homework Helper

    You've got:
    Which is a quadratic equation in [tex]y[/tex].
    Apply the quadratic formula, and you should get there.
  4. Feb 22, 2004 #3
    Multiply through by y and you have a quadratic equation in the y variable.

  5. Feb 23, 2004 #4

    I should have seen this. It's a no brainer. Where was my brain last night?[zz)]
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