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Homework Help: What kind of problem is this. (Seperable or Bernoullis) / Diff EQ

  1. Oct 10, 2012 #1
    1. The problem statement, all variables and given/known data

    xy^2 dy/dx = y^3 - x^3 , y(1) = 2

    2. Relevant equations

    3. The attempt at a solution

    It says to solve the initial value problem. I am assuming it is not a Bernoulli, but I can't seem to separate it. What should I do?


    This is what I get when I separate it, is this right?

    y^2-y^3 dy = -x^2 dx
  2. jcsd
  3. Oct 10, 2012 #2


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    xy^2 dy/dx = y^3 - x^3
    dy/dx = y/x - x^2/y^2
  4. Oct 10, 2012 #3


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    How do you get that last line?

    It should be y2 dx - y3 dy = -x2 dx, which is not separated.

    Try the substitution, y = xv .
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