complex equation solving



Dear List,

I have just started to use maxima and am finding it extremely useful.  My
area of expertise is quite far from mathematics, so am struggling with the
documentation to solve the following problem.

I need to solve for u in:


			    x - 1	     x	      b u
		     (u - t)	  x   (u - t)  (a b %e	  + 1)
		 0 = -------------- - ------------------------
			  b u		        b u     2
		      a %e    + u	   (a %e    + u)


which I assigned to f1.  Solving for u is complicated by the exponential
term, so trying solve(f1, u) gives:


		   1 - x    b u		    x		 x - 1		   x
	    (u - t)      (%e    (a b (u - t)  - a (u - t)      x) + (u - t) )
       [u = -----------------------------------------------------------------]
					    x


which is not useful.  I would appreciate any guidance on how to solve this
equation.  Thanks in advance.



Cheers,

-- 
Seb