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Homework Help: Solution Of A Differential Equation]

  1. May 8, 2008 #1
    Hi all I was wondering if i could get some help with this.

    1. I need to be able to solve a second order differential equation,

    2. d^2(y)/dx^2= c/x

    where c is an arbitary constant.

    I was thinking that the solution would take form of a trigonometrial eqauation, would this be correct?

    Thanks for your time

    N



    3. The attempt at a solution
     
  2. jcsd
  3. May 8, 2008 #2

    D H

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    You left this part of the template blank. What work have you done on the problem?
     
  4. May 8, 2008 #3

    MathematicalPhysicist

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    Well it's quite easy, here's a hint: succesive 'something' will do the trick.
     
  5. May 8, 2008 #4

    HallsofIvy

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    WHY would you tnink "that the solution would take form of a trigonometrial eqauation"?
     
  6. May 8, 2008 #5

    tiny-tim

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    Hi NEWO! :smile:

    Noo … you're thinking of d²y/dx² = -cy.

    Hint: just say the equation in ordinary English:

    "y is a function of x, and if you differentiate it twice, you get c/x." :smile:
     
  7. May 8, 2008 #6

    HallsofIvy

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    If you let [itex]v= dy/dx[/itex] then [itex]d^2y/dx^2= dv/dx[/itex] so your equation becomes [itex]dv/dx= c/x[/itex]. What is v(x)?
     
  8. May 9, 2008 #7

    MathematicalPhysicist

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    Halls, isn't your hint really the solution?
     
  9. May 9, 2008 #8

    HallsofIvy

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    Well, almost. There is still a tiny amount of work to be done. And I suspect that "NEWO" won't bother to come back to look at the responses.
     
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