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Athematica seems to be asking for more arguments

  1. May 10, 2007 #1


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    1. The problem statement, all variables and given/known data

    I'm fairly new to mathematica and have been trying to input the following equation, but keep getting an error message stating that I have only 2 arguments when I need 3 or more.

    BTW, this is in relation to astrophysics

    2. Relevant equations

    function is:

    f(x) = (1 / x^2) d / dx ((x^2) (df^(E-1) / dx))

    where ϵ=5/3
    and f(0) = 1

    3. The attempt at a solution

    I've put it into mathematica as

    DSolve[{f[x] == ((1/x^2))* (d/dx) (x^2 * df^(ϵ - 1)/dx), x[0] == 1} f[x], x]

    I've had do tidy this up a bit as when cutting & pasting mathematica seems to add extra brackets etc.

    As I've stated, mathematica seems to be asking for more arguments, but I don't know what else I can add to the equation.

  2. jcsd
  3. May 10, 2007 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    Mathematica does not understand the symbol (d/dx). You need to use the D[] operator to perform differentiation.

    - Warren
  4. May 10, 2007 #3


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    so, I should differentiate the inner bracket first and then add the answer to this in a second differentiation??
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