Pas directement. Mais, en supposant que Maxima arrive à trouver les
racines du polynomial, il est facile à faire.  Attention!  La méthode
démontrée ne prend pas compte des eventuels polynomiaux où Maxima ne
trouve pas les racines explicites.

poly: x^4-x-1$

sols: solve(poly,x);
 [x = 
-sqrt((3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2)+6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2))*%i
    
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4))
    
-sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)),
  x = 
sqrt((3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2)+6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2))*%i
    
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4))
    
-sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)),
  x = 
sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6))
    
-sqrt(6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2)-(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2))
     
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4)),
  x = 
sqrt(6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2)-(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2))
    
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4))
    
+sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6))]

fact: xreduce("*",makelist(x-rhs(q),q,sols));
  
(x-sqrt(6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2)-(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2))
     
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4))
    
-sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)))
   
*(x+sqrt(6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2)-(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2))
       
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4))
      
-sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)))
   
*(x-sqrt((3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2)+6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2))*%i
       
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4))
      
+sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)))
   
*(x+sqrt((3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(3/2)+6*sqrt(3)*sqrt(3^-(3/2)*sqrt(283)/2+1/2))*%i
       
/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)*(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)^(1/4))
      
+sqrt(3*(3^-(3/2)*sqrt(283)/2+1/2)^(2/3)-4)/(2*sqrt(3)*(3^-(3/2)*sqrt(283)/2+1/2)^(1/6)))

expand(%);

x^4+(3*(sqrt(283)/(6*sqrt(3))+1/2)^(2/3)-4)^(3/4)*sqrt((3*(sqrt(283)/(6*sqrt(3))+1/2)^(2/3)-4)^(3/2)

+6*sqrt(3)*sqrt(sqrt(283)/(6*sqrt(3))+1/2))*%i*x
          /(12*sqrt(3)*sqrt(sqrt(283)/(6*sqrt(3))+1/2))
         
-(sqrt(283)/(6*sqrt(3))+1/2)^(1/6)*sqrt((3*(sqrt(283)/(6*sqrt(3))+1/2)^(2/3)-4)^(3/2)

+6*sqrt(3)*sqrt(sqrt(283)/(6*sqrt(3))+1/2))*%i*x
           etc. etc.

radcan(%),algebraic:true;
x^4-x-1



On Dec 9, 2007 2:14 PM, Valere Bonnet <[EMAIL PROTECTED]> wrote:
> j'aimerais savoir s'il est possible d'utiliser maxima pour factoriser des
> expressions avec
> des radicaux; par exemple: $x^2-2\sqrt3+3$ ; deviendrait: $(x-\sqrt3)^2$.

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