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I am having trouble solving a set of equations in mathematica. I do not get any errors, but i don't get any answers as well.

I have some restrictions on my parameters and variables in the equations which i try to implement too. I have tried to implement them using $Assumptions and Assuming[], but it seems like Mathematica ignore it. However, all my parameters and variables are real and non-negative. g is a known positive constant which i define earlier in my notebook.

Here is what i type in Mathematica 8 (this is copy-pasted from my program):

g:=6.45161;
Solve[{u == 1/3 μb - 2/3*e, d == 1/3 μb + 1/3*e, 
2*(u^2 - (g x/2)^2)^(3/2) - (d^2 - (g x/2)^2)^(3/
     2) - (d^2 - (g y/Sqrt[2])^2)^(3/2) - (e^2)^(3/2) == 0, 
x >= 0, y >= 0,μb > e, μb >= 0, u >= 0, d >= 0, e >= 0}, {u, d, e}, 
Reals]

μb is a parameter and x and y are variables in some other functions. So what i want is for u,d and e to be functions of x and y, and dependent of μb. Is there an easy way to solve this in Mathematica 8?

This is my first post here, so please let me know I make things unclear or something. I have tried to find the solution elsewhere, but have not succeeded.

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In what way this this fail? Did you get errors? Did it run for a long time without a result? –  Mr.Wizard May 11 '13 at 9:14
    
It runs a long time without a result. I do not get any errors though. –  user7328 May 12 '13 at 8:51
    
Unless you have numerical values of x and y it looks like a pure algebraic solution of this is unlikely. –  Jonathan Shock May 13 '13 at 4:29
    
Ok. Thanks for the answer. So i probably need to assign values for x and y in a loop and solve theese equations many times and eventually make an InterpolatingFunction for u and d? I know what values x and y should take for different [Mu]b, so i guess this is an alternative at least. Or do you see a faster or easier way out? –  user7328 May 14 '13 at 9:22
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