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 ********************************************************************* --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---