Texas Instruments TI-89 Titanium Graphing Calculator

Before I bought a TI-89 Titanium, I had used a TI-83 Plus for four years. After taking calculus and learning about limits, derivatives, integrals, infinite series, Taylor series, differential equations, and multivariable functions, I decided that I would look for a calculator which was capable of symbolic computation. After analyzing my options, I decided on a TI-89 Titanium. The TI-89 Titanium is able to expand polynomials, factor polynomials, and do all of the calculus techniques that I mentioned — symbolically and numerically. One of the other things I found helpful was the TI-89 Titanium’s ability to plot direction fields using different algorithms (including Euler’s method). One of the nicer things about this model (compared to the TI-89) is that it has USB connectivity (cord included) for installing applications and transferring data. Another nice thing is that it also supports connectivity to older model TI-89s via the old I/O port which is right next to the USB connector. I also found the “exact mode” very useful (exact mode will give you exact answers rather than decimal approximations). Yet, the most useful feature of this calculator is probably the “pretty print” feature which displays expressions as you would normally write them on paper. This feature allows you to easily see the expression that you typed in. All these features plus copy and paste ability make this calculator nearly perfect. My only complaint is that the cover does not initially slide on and off easily. However, I’m sure that with more use it will wear in. Overall this is a great calculator — I recommend it (more…)