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Math Help - why cant it be solved?

  1. #1
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    why cant it be solved?

    d2y/dx2 + (x^2)(y^2) = x, y(0) = y(2) = 0

    why cant this be solved algebraically? or can it?

    and if so, how?

    many thanks
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  2. #2
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    That's a rather badly non-linear equation. Typically such equations do NOT have what you call an "algebraic" solution. A better question would be a 'why should it have such a solution?"
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  3. #3
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    ok.. but why should I be able to tell i cant solve it?

    why could you tell that it couldnt be solved algebraically?

    thanks
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  4. #4
    MHF Contributor

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    I thought that I had just answered that! Only very special (very carefully set up) non-linear equations can be solved "exactly".
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  5. #5
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    sorry to be persistent.. I just want to make sure I understand exactly

    so how could you tell straight away that it couldnt be solved? is there a name for such equations? what characteristics make it such that it cant be solved?

    many thanks - much appreciated
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  6. #6
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    I believe it is because the second y term is non-linear. A requirement to solve unless it's a special case.
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