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Homework Help: Horrible expression involving logs and inverse tan functions

  1. Jul 9, 2011 #1
    1. The problem statement, all variables and given/known data

    [tex] \frac{d^2y}{dx^2} + (y^4-1)\frac{dy}{dx} = 0 [/tex]

    2. Relevant equations

    [tex] \frac{dy}{dx} + (y^4-1) = 0 [/tex]

    3. The attempt at a solution

    [tex] \frac{dy}{dx} = (1- y^4) [/tex]
    [tex] \frac{dy}{1- y^4} = dx [/tex]

    Then I get a horrible expression involving logs and inverse tan functions on the LHS and x + A on RHS ???

    sorry heading should be ODE not PDE
    Last edited by a moderator: Feb 4, 2013
  2. jcsd
  3. Jul 9, 2011 #2
    Re: Pde

    You have the wrong expression after the integration, try taking the derivative of that with respect to x to see if you get the same expression as you started with. HINT: You forgot the x to y dependence.
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