On Fri, Nov 7, 2008 at 8:52 PM, Gary <[EMAIL PROTECTED]> wrote:
>
> Hello all :-)
>
> I'm new to sage and to this group.
>
> I teach at a two-year college and have been exploring the
> possibilities of incorporating sage into some of my classes. On my
> laptop I also have Mathematica and Matlab installed and have used
> Maple in the past as well.
>
> I started experimenting with sage because it would provide a free
> (yay!) alternative to the programs mentioned above; this is a big plus
> for my students already burdened with the high cost of their
> textbooks. With the small amount of exposure to sage I've had so far,
> I can say that I find it useful and powerful. It is also, to me,
> confusing at time but to be fair so too are Mathematica and Maple.
>
> Now to the problem at hand.
>
> I've been trying to evaluate a symbolic double integral but am
> perplexed by the unevaluated tan(pi/2) expressions in the result since
> tan(pi/2) is undefined. What am I missing here and what do I need to
> do to get this to evaluate to the correct value of
> (4*pi - 3*sqrt(3))*a^2/6?
>
> Thanks much,
> Gary
>
> sage input:
> ***************************************************************
> var('a r theta')
> assume(a > 0)
> integral(integral(r, r, a*csc(theta), 2*a), theta, pi/6, pi/2)
> ***************************************************************
>
> sage output:
> *********************************************************************
> (2*pi*tan(pi/2) + 1)*a^2/(2*tan(pi/2)) - (2*pi + 3*sqrt(3))*a^2/6
> *********************************************************************
>Maxima actually does all the symbolic integration in Sage, currently, so I've forwarded your email to Robert Dodier -- lead developer of Maxima. William > > > > > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
