solve in Maxima



------------------------------

This is the first reply email  from Fujio KIDA in Japan to CAS on the
attached luigi's email.

I tried and could find three distinct solutions by adding "dummy variable
a=1" as follows;

solve([
0=35*x^3+(35*sqrt(3)-9)*x^2-(9*sqrt(3)+2)*x-2*sqrt(3) ,
a=1
],[ a,x]);

As Mr luigi said, Maxima sometime does not give the answers as we hope.
      (I have benefited quite a lot from using Maxima, and much better than
"Mathematica" for my purposes.)

Also, Maxima gave three solutions in complex formula as expected for the
third order polynomials.

Fujio KIDA




  ???:     luigi_marino2 at alice.it
<http://www.math.utexas.edu/mailman/listinfo/maxima>;

  ??:       maxima at math.utexas.edu
<http://www.math.utexas.edu/mailman/listinfo/maxima>;

  ??:       2011/08/12 16:51

  ??:       [Maxima] solve in Maxima






Maxima cannot exactly solve this polynomial
with not-rational coefficients:
35x^3+(35*sqrt(3)-9)x^2-(9*sqrt(3)+2)x-2*sqrt(3)
the real solutions are:
-sqrt(3) , -1/7 , 2/5
the only method is:
divide(
35x^3+(35*sqrt(3)-9)x^2-(9*sqrt(3)+2)x-2*sqrt(3),x-2/5)
and then
solve(%,x)
Best regards
Luigi Marino_______________________________________________

***********************************************************************

(%i1) eq:35*x^3+(35*sqrt(3)-9)*x^2-(9*sqrt(3)+2)*x-2*sqrt(3)=0$
(%i2) factor(eq,a^2-3);
(%o2) (x+sqrt(3))*(5*x-2)*(7*x+1)=0
 or
(%i3) gfactor(eq);
(%o3) (x+sqrt(3))*(5*x-2)*(7*x+1)=0
(%i4) solve(%);
(%o4) [x=-1/7,x=2/5,x=-sqrt(3)]

(%i5) build_info()$
Maxima version: 5.25.0
Maxima build date: 12:0 8/2/2011
Host type: i686-pc-mingw32
Lisp implementation type: Clozure Common Lisp
Lisp implementation version: Version 1.7-r14925M  (WindowsX8632)

Aleksas D