%i3) f:-x**3+x+0.25;
3
(%o3) - x + x + 0.25
(%i4) allroots(f);
(%o4) [x = - .2695944364054446, x = - .8375654352833231, x =
1.107159871688768]
(%i5)
Le 13/10/2010 21:16, egc a ?crit :
> After 15+ years of using Maple, I've decided to take latest build of
> Maxima for a spin (motivated to some degree by the desire to find a
> symbolic algebra program I can have my students use at no cost). I've
> done a a bit of 'fooling' with Maxima (learn by doing), and am stuck
> on something which seems pretty trivial.
>
> Consider f : -x^3+x+0.25=0
>
> Now, I know from Maple that the roots of this polynomial are -0.83757,
> -0.26959, and 1.1072. However, in Maxima, if I try
>
> solve(f,x);
>
> I get something is is bizarrely large and convoluted -- all sorts of
> fractions, and square roots, and the like. I tried toggling different
> levels of float, but I still don't end up with a nice simple solution
> vector containing these three solutions.
>
> Pointers to the obvious solution? Thanks in advance (remember, newbie,
> more or less, so set phasers to 'singe only'). ;-) I'll leave my
> implicit differentiation question to a followup post. ;-)
>
>
> _______________________________________________
> Maxima mailing list
> Maxima at math.utexas.edu
> http://www.math.utexas.edu/mailman/listinfo/maxima