• what is solution of y'-y^2-x^2-1=0 ? it seems wolfram solution is wrong

    From drhuang57@gmail.com@21:1/5 to All on Thu Feb 4 15:56:07 2021
    what is solution of y'-y^2-x^2-1=0 ?
    it seems wolfram solution is wrong?

    mathHand.com

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  • From Nasser M. Abbasi@21:1/5 to drhu...@gmail.com on Thu Feb 4 18:25:12 2021
    On 2/4/2021 5:56 PM, drhu...@gmail.com wrote:
    what is solution of y'-y^2-x^2-1=0 ?
    it seems wolfram solution is wrong?

    mathHand.com


    I happend to have solved this ode allready, but with +1
    instead of -1. It is ofcourse a RICCATI ODE. The solution
    follows the same algorithm.

    You can find the solution here

    https://www.12000.org/my_notes/solving_ODE/current_version/insu3821.htm

    For -1, instead of +1, the solution is

    ===========
    ode:=ode:=diff(y(x),x) -x^2-y(x)^2-1=0;
    y(x) = 1/2*((-3+I)*_C0*WhittakerM(1-1/4*I,1/4,I*x^2)+4*WhittakerW(1-1/4*I,1/4,I *x^2)+(-2*I*x^2+1-I)*_C0*WhittakerM(-1/4*I,1/4,I*x^2)+(-2*I*x^2+1-I)*WhittakerW (-1/4*I,1/4,I*x^2))/x/(WhittakerW(-1/4*I,1/4,I*x^2)+_C0*WhittakerM(-1/4*I,1/4,I *x^2));
    odetest(mysol,ode);
    0
    =================

    Wolfram alpha solution is again wrong. It looks like Wolfram alpha
    has a bug with Riccati ODE's. You might want to consider reporting
    these to them so they can fix it.

    --Nasser

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