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Polymath or Matlab non-linear algebraic solver

  1. Oct 11, 2013 #1

    I am having difficulty inputting a non linear algebraic equation into polymath to solve

    for reference the equation is

    x*(100-.5*x)^0.5/(15-x)/(20-.5 * x)^0.5 - 87.824 == 0

    and I want to solve for x, but haven't gotten anything. Also I don't know how to program it into matlab. Anyone that can help?? Thank you
  2. jcsd
  3. Nov 21, 2013 #2


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  4. Nov 21, 2013 #3


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    It could be that the software is having trouble parsing your equation as it is written. Don't skimp on parentheses.
  5. Nov 22, 2013 #4


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    Unless you explicitly want matrix power or matrix multiply, I recommend using the array operators exclusively.
    Code (Text):

    fun = @(x) x.*(100-0.5.*x).^0.5./(15-x)/(20-0.5.*x).^0.5 - 87.824;
    When I plotted this function, I did not find any real solutions for x. If it has any, they are complex.
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