Hi, On Thu, Sep 18, 2008 at 2:25 PM, William Stein <[EMAIL PROTECTED]> wrote: > [...] > This will be going on the main sagemath.org webpage, and could be a > superb way of getting > students really interested in sage. I wonder if somebody could > volunteer to read through > the tutorial and make some comments, find typos, etc.? It's fun, not > too long, etc.
>From the "Limits" page at http://sage.math.washington.edu/home/elliottd/calctut/limits.html below are some typos and suggestions. While working through the tutorial at the above page, I used Sage 3.1.1. [1] You might want to rewrite the sentence "Presuming that you have the Notebook open, go ahead and create a new worksheet." as "Assuming that you have the Notebook open, go ahead and create a new worksheet." [2] For the graph at http://sage.math.washington.edu/home/elliottd/calctut/pix/calctut/limits02.png I entered the same code and got a similar image, but mine has a red dot rather than just a black circle. [3] You might want to rewrite the sentence "To find this value algebraically, though, we can actually remove the discontinuity, which is to say we can factor the numerator, then divide both the top and the bottom by (x - 1) to find that... " as "To find this value algebraically, we can remove the discontinuity by factoring the numerator, then divide both the top and the bottom by (x - 1) to obtain:" [4] For "Practice Problems" number 2, the problem limit at (1) http://sage.math.washington.edu/home/elliottd/calctut/pix/calctut/limits06.png is different from the expression in the plot command: (2) plot((1 - cos(x)^2)/sin(x)+1, x, -1, 5).show(xmin=0, ymin=0) I think you're trying to ask students to find the limit of the expression (1 - cos(x)^2) / sin(x) at x = pi but you're also giving Sage code to plot the expression (1 - cos(x)^2) / sin(x) + 1 But the limit of the expression in (1) is 0, since we're using this command limit( (1 - cos(x)^2) / (sin(x)), x = pi ) Accordingly, we can change the plot command (2) to this: plot( (1 - cos(x)^2) / sin(x), x, -1, 5).show(xmin=0, ymin=0) -- Regards Minh Van Nguyen Web: http://nguyenminh2.googlepages.com Blog: http://mvngu.wordpress.com --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@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-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
