This isn’t at all a post I was planning to do, but again tonight I had another question on the Tech Powered Math Facebook page about the TI-84+C and asymptotes. If you press 2nd and FORMAT, you’ll find an option called “Detect Asymptotes” that can be turned on or off. The people I’ve heard from seem to assume that this feature will find and define asymptotes for users, but from my experience I don’t believe it functions this way.
Let me preface this by saying that this isn’t a feature that I heard mentioned at any official briefings I received from Texas Instruments or at the T3 International Conference in Philadelphia. However, based on my own experimentation, it appears that asymptote detection will either correctly turn off the trace of the asymptote of a function when asymptote detection is turned on, or it will turn on the trace when asymptote detection is turned off. You can see this in the example above, which is the graph of y=1/(x-2). On the left, I have turned asymptote detection off. On the right, I have turned it on. If I find out I’m wrong and the TI-84+C is capable of actually calculating the asymptotes for the user, I will update this post.
This is also probably as good as time as any to let you know that I am almost done wrapping up work on my TI-Nspire DVD and hope to begin work on my TI-84+C DVD this week. I (optimistically) hope to have them both available for sale by mid-August if not a bit sooner. These are targeted primarily at beginning to intermediate users of these calculators. I know many regular readers of Tech Powered Math are more advanced than that, but I also bet some of you know friends or colleagues who are still getting started and could use a resource like that. Stay tuned because I will have a big but brief kick off sale on both DVD’s when they launch on Amazon for my Facebook, Twitter, and email subscribers.