<p>I just bought a TI-84 Plus on sale from Staples. I think this will work, but should I return it for a higher-level one to avoid having to eventually buy one in the years ahead anyway?</p>
<p>I had an 83+ and an 89, and let me tell you the integral and derivative functions on the 89 are every calculus student’s best friend. I understand that the 84+ is basically an 83+ with more memory and a fancy case, so you shouldn’t have a problem doing engineering math with it. However, when I got my 89 from Staples last year it was only $20 more than the 83+. If Staples still has that same discount, I highly recommend you trade up to the 89. But if you are planning on taking statistics I heard from my friends in that class that the 89 was missing some statistics functions. Can anyone else verify this? In summary, the 89 is awesome.</p>
<p>But these intergral and derivative functions are something built into the TI-89, not a program I can load onto my TI-84+</p>
<p>eh…not sure if that last bit was a question hehe. it’s a computer algebra system (CAS) that allows the 89 to do indefinite integrals and derivatives, etc. i don’t know much of that is exclusive to the software and hardware of the 89, but it would seem to me the ability to treat variables as entities without values as something basic to the system. i dont think i’ve ever seen an 83, programs and all, with the ability to do anything nearly as impressive as an 89.</p>