Re: [fricas-devel] Re: Selection of roots

Martin Rubey <[email protected]> 03 Nov 2008 23:14:30 +0100

Newsgroups	gmane.comp.mathematics.axiom.general,gmane.comp.mathematics.open-axiom.devel
Message-ID	<[email protected]>

Alejandro Jakubi <[email protected]> writes:
> Now, my next question is about selecting the two real roots out of the four
> produced by 'radicalSolve' here:
> 
> f:=(x^3+x^2-4*x-4)/(2*x^2+7*x-4)
> fp:=differentiate(f,x)
> radicalSolve(fp,x)
> 
> The problem is that
> 
> allRootsOf(fp)$RealClosure(Fraction Integer)

try

allRootsOf(numer fp)$RealClosure(Fraction Integer)

Martin