The New MathPrint on the TI-84 Calculators

This past week Texas Instruments released a new operating system (OS) for their TI-84 series of calculators.  The new operating system is free, free is good in education. 

It surprised me to see this new release.  I have owned my TI-84 for at least five years, making it long past when I thought I would see a major change in the OS.  The new operating system has a feature called MathPrint that displays the mathematics on the calculator screen in a format that more nearly matches what you would see in a textbook.

Figure 1 below is what the calculation of the sum of the numbers from 1 to 100 looked like on the previous OS that was originally released with the calculator.  On the right is what the calculation of the sum of the numbers from 1 to 100 looks like in the new OS.

   

               Figure 1                               Figure 2

Working from the idea that distance is the integral of the velocity, the calculation for the distance an object that is released from rest falls under the influence of the Earth's gravity in ten seconds would be:

What this looks like in the old operating system is in Figure 3, in the new operating system is in Figure 4

   

               Figure 3                                Figure 4

I think it may take a bit more time to enter expressions in the new operating system, but I think that will be time well spent.  When writing equations in physics you can better illustrate the physics behind the mathematics if you can keep the numbers and the expression in the equation written in a form that corresponds to the role those numbers play in the original problem. 

Let me illustrate this in a task as simple as graphing the motion of a long pendulum that completes 1 cycle every 5 seconds and has an amplitude of 1/2 of a meter.  From mathematics, students will know that 1 cycle is 2 pi radians.  But there are several equations that come to bear on this problem.

It is not all that obvious how the numbers in the problem go into the equations above, but by simple recalling that omega is the angular rate of rotation and is measured in radians per second, it seems very natural to say that we cover  2 pi radians per every 5 seconds.  That translates rather easily into the expression:

 

When t = 5, we have completed one revolution (2 pi).  When t = 10, we have completed two revolutions (4 pi).  With that in place it seems reasonable to write:

The beauty of writing it in this form rather than as

is that it then allows you to see the physics.  As t goes up we wind off more and more revolutions.  If the 5 became a 10, then it would take 10 seconds to make one revolution.  And let's look at the screen shots in the two different operating systems.

   

The new operating system can be downloaded from TI's web site, by going directly to this link.  The operating system is called "v 2.53MP".

I believe seeing the math in this form on their calculators would help students.

If you want the next blog to talk more about how you get the new operating system off the Internet into your calculator, drop a note in the comment section below for this blog post.

In future posts, I'll plan to spend some time talking about other resources TI has for physics on their web site.