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Homework Help: Finding a constant for a partial differential equation

  1. Nov 30, 2005 #1
    Can anyone help me with this question? I tried taking the derivative of u with respect to x and then summed the third derivative, but I'm getting nowhere. Any help would be great, thanks.

    Let u(x1, x2, … , xn) = http://img480.imageshack.us/img480/1694/image0027hm.gif [Broken],[/URL] where a is a constant, and n is given.

    Find all the values of the constant a, if any, for which the function u satisfies the partial differential equation http://img480.imageshack.us/img480/2918/image0044jl.gif [Broken] .
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Dec 4, 2005 #2


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    Do you think it's possible that you should be making a substitution for the sum of x_i squared? It just seems that polar coordinates might be an easier way to work the problem. Not that it would be easy.


    Now. How do I make that little "lightbulb" that I accidentally clicked on go away?
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