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Homework Help: Specific solution of diff eq, no initial value

  1. Aug 25, 2012 #1
    1. The problem statement, all variables and given/known data
    Consider the differential equation
    059b0fc5ef0cd85a055fc8a05eef301.png

    Find a general solution to this differential equation that has the form
    c1403c12bfdafbad58b32041c1e5381.png
    .
    .
    .
    y = Cx3

    Find a second solution c1403c12bfdafbad58b32041c1e5381.png that might not be a general solution and which may have a different value of n than your first solution.


    3. The attempt at a solution
    I solved the first part of the problem
    y = Cx3

    But am at a complete loss for how to find a second explicit solution without being given an initial value.
     
    Last edited: Aug 25, 2012
  2. jcsd
  3. Aug 25, 2012 #2

    LCKurtz

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    I'm guessing ##y=0## isn't what is being wanted here although it is a solution.

    Question: Is ##y = |x|^3## a solution?
     
  4. Aug 25, 2012 #3

    HallsofIvy

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    Why would you guess that? [tex]y= 0x^n[/tex] is a solution for any n.
     
  5. Aug 25, 2012 #4

    LCKurtz

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    Are you addressing me? Yes, I know it is a solution for any n, as I said. But, given the poor wording of the question, I thought they might be looking for the more interesting ##y = |x|^3##.
     
  6. Aug 26, 2012 #5
    I've tried y=0 and y=e^c(x^3), I'll see if it accepts y=0x^n but I think they're looking for a specific n


    edit: 0x^n was it! Thanks!
     
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