On 02/11/2010 07:10 AM, Andrej Vodopivec wrote:
> I'm sure there are other possibilities, but here are two simple options:
>
> (%i1) subst(y = m*x +b, (x-2)^2 + (y-3)^2 = 5), expand;
> (%o1) m^2*x^2+x^2+2*b*m*x-6*m*x-4*x+b^2-6*b+13=5
> (%i2) rat(%o1, x);
> (%o2)/R/ (m^2+1)*x^2+((2*b-6)*m-4)*x+b^2-6*b+13=5
> (%i3) load(format)$
> (%i4) format(%o1, %poly(x));
> (%o4) (m^2+1)*x^2+(2*b*m-6*m-4)*x+b^2-6*b+13=5
Oh my god! Why was I not informed about this format thing before? :-)
That seems super-useful. How well supported is it? There are some
various warnings in the README. Sigh, Maxima always has some hidden
features somewhere that do just what I want except I don't know about them.