Solving polynomials with Maxima ?



Your "polynomial" is of degree 3 in x^(1/2).
 
I suggest you make the change of variables t=x^(1/2) and solve
 
a*t^3-b*t^2+c*t-d=0.
 
This can be solved for t by solve(......,t);
 
then take the square root of the answer. This will give you 6 solutions (+
and - sqrt).
 
I hope this helps.
 
(The symbolic solution to a cubic like this is generally very complicated
and not of much use.)
 
 


  _____  

From: maxima-bounces at math.utexas.edu [mailto:maxima-bounces at math.utexas.edu]
On Behalf Of Laure.DUTOIT at cepal.org
Sent: Monday, September 22, 2008 3:10 PM
To: maxima at math.utexas.edu
Subject: Solving polynomials with Maxima ?



Dear all, 

I am trying to solve a polynomial using Maxima, but I cannot get an explicit
answer. My polynomial is of the following form: 
x^(3/2) a - x b + x^(1/2) c - d =0, where a,b,c and d are composed of
several variables, but are not of interest. 

So, I would like to be able to solve this polynomial (I am not a
mathematician, but I think solving such a polynomial is feasible using a
mathematical software, no ?) using Maxima to get to an answer of the form
x=f(a,b,c,d) and not x=f(a,b,c,d,x), as I now get using the command "solve"
(i.e, the answer I am given is not explicit).