On Thu, Nov 09, 2006 at 05:38:20PM -0800, Richard Fateman wrote:
> There are 3 cube roots. Maple gives one. Maxima gives another (the
> real-valued one). Neither one is entirely correct.
>
> If Maxima gave the same one as Maple, someone would report it as a bug.
> Someone who had not yet learned about complex numbers, perhaps.
>
> The message about sqrt(x^2) is relevant here.
It's been a long day.... sigh.
I kept thinking that the cube root of 5/3 would never fall on the
negative real axis no matter how many solutions there were... so
maxima must have done something wrong...
of course it's the cube root of -5/3 I was supposed to be considering...
here's a more pointed question...
shouldn't (-a/b)^(c/d),numer;
%^(d/c);
give (-a/b) back by default?
an example:
(%i5) (-5/3)^(14/37),numer;
(%o5) 1.213228964673703
(%i6) %^(37/14);
(%o6) 1.666666666666667
Being tired I'm not quite sure if it's possible to easily guarantee this.
--
Daniel Lakeland
dlakelan at street-artists.org
http://www.street-artists.org/~dlakelan