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Mathematica: Solve error

  1. Jan 15, 2014 #1
    Here is my code
    Code (Text):
    Nl = 10^(49) ;
    Nh = 100 ;
    b = 4*10^(-13) ;
    Rs = N[((3 Nl)/(4 Pi b Nh^2))^(1/3)];
    a = 6*10^(-18) ;

    Solve[x/(4 Pi r^2)  E^(-Nh a x) a Nl == (1 - x)^2 b Nh,

    When I run it, it shows the error:
    "Solve::nsmet: This system cannot be solved with the methods available to Solve. >>"

    How can I solve this equation? Thanks.
    Last edited: Jan 15, 2014
  2. jcsd
  3. Jan 15, 2014 #2
    Since you have an undetermined parameter, Mathematica tries to find an analytic solution, which I don't think will work in this case. If you know the value of r, then a numerical solution is possible (assuming x is a real number).
  4. Jan 15, 2014 #3
    Thanks for your reply. Do you know any way to plot this (x vs. r) in mathematica? x should be some value between 0 and 1, and r is a positive number.
  5. Jan 15, 2014 #4
    The Plot3D command should be useful.
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