Intriguingly, you can simply full_simplify *again* to get what you want:
sage: var('u,v')
(u, v)
sage: r = vector([u*cos(v), u*sin(v), v])
sage: ru = diff(r,u)
sage: rv = diff(r,v)
sage: n = ru.cross_product(rv)
sage: n
(sin(v), -cos(v), u*sin(v)^2 + u*cos(v)^2)
sage: norm(n)
sqrt(abs(u*sin(v)^2 + u*cos(v)^2)^2 + abs(-cos(v))^2 + abs(sin(v))^2)
sage: f = norm(n).full_simplify()
sage: f
sqrt(u^2 + sin(v)^2 + cos(v)^2)
sage: f.full_simplify()
sqrt(u^2 + 1)On Tue, Jan 24, 2012 at 9:01 AM, Juan Carlos Bustamante < [email protected]> wrote: > Hi all, > > I'm trying to make some camputations to show to my students, but SAGE > won't simplify sin^2 + cos^2 = 1. > > What am I doing wrong? > [image: Sage-trig.png] > > Regards, > > JC > > -- > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/sage-support > URL: http://www.sagemath.org > -- William Stein Professor of Mathematics University of Washington http://wstein.org -- To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
<<Sage-trig.png>>
