Solving a single equation of two variables

I don't think you've done anything wrong; I don't think that you've found 
a Maxima bug either.
It seems to me that the solution to your equation is either a huge mess or 
it  doesn't have a reasonable 
representation.    (I think the second possibility is the correct one, but 
 I could be wrong.)  Neither 
commercial Macsyma or the Maple  (a somewhat out-of-date version)  give an 
explicit solution to your 
equation. 

Suggestion:  Rescale your equation with x -> a * x and r -> a * r.  You'll 
be able to eliminate a from your 
equation.  After that you can study your equation graphically and 
numerically.

Barton




Herbert_Desson@jltgroup.com
Sent by: maxima-admin@math.utexas.edu
09/16/2003 09:09 AM

 
        To:     maxima@math.utexas.edu
        cc: 
        Subject:        [Maxima] Solving a single equation of two variables


I am new to maxima and am trying to solve the following relatively simple
equation for r:
    x = a * log(( a + sqrt( a^2 - r^2))/r) - sqrt(a^2 - r^2),

where x and r are variables and a is a constant.



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