• wolfram gives wrong solutions

    From drhuang57@gmail.com@21:1/5 to All on Fri Jan 15 17:12:57 2021
    y''-y' y-x=0
    y''-y' y-2x=0
    y''-y' y-3x=0
    ......
    y''-y' y -c x=0, where c is constant, 1,2,3, .....
    wolfram always give 2/(c1-x)
    y''-2y' y-x=0
    y''-2y' y-2x=0
    y''-2y' y-3x=0
    ......
    y''-2y' y -c x=0, where c is constant.
    wolfram always give 1/(c1-x)
    y''-b y' y-x=0
    y''-b y' y-2x=0
    y''-b y' y-3x=0
    ......
    y''-b y' y -c x=0, where b, c are constants.
    wolfram always give 2/(c1-x)/b
    Obviously all these solutions are wrong. How to check solution in wolfram?

    what is solution and how to check by your online software?
    Input your diff equation into mathHand.com, click the "dsolve" button to solve, then click the "test" button to test solution.

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  • From drhuang57@gmail.com@21:1/5 to drhu...@gmail.com on Sat Jan 16 17:51:45 2021
    On Saturday, 16 January 2021 at 12:12:59 UTC+11, drhu...@gmail.com wrote:
    y''-y' y-x=0
    y''-y' y-2x=0
    y''-y' y-3x=0
    ......
    y''-y' y -c x=0, where c is constant, 1,2,3, .....
    wolfram always give 2/(c1-x)
    y''-2y' y-x=0
    y''-2y' y-2x=0
    y''-2y' y-3x=0
    ......
    y''-2y' y -c x=0, where c is constant.
    wolfram always give 1/(c1-x)
    y''-b y' y-x=0
    y''-b y' y-2x=0
    y''-b y' y-3x=0
    ......
    y''-b y' y -c x=0, where b, c are constants.
    wolfram always give 2/(c1-x)/b
    Obviously all these solutions are wrong. How to check solution in wolfram?

    what is solution and how to check by your online software?
    Input your diff equation into mathHand.com, click the "dsolve" button to solve, then click the "test" button to test solution.

    more and more examples are in
    http://drhuang.com/index/ode

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