<p>If I had two calculators, say a ti-84 and ti-89, could I bring both and use both during the test? I'm very comfortable using the ti-84, but if necessary (for solving equations, zeros, intercepts) I will refer to the 89.</p>
<p>yes you can. however, you dont really need it...everything you want to do can be done on the ti 84.</p>
<p>Additionally, how do I enter formulas to save them in my calculator?</p>
<p>you could bring both. There are practical reasons for this, actually. The TI-89 graphs very slowly and you could bring the TI-84 for more RAM....to write formulas you would need to code them with your calculator.</p>
<p>You are allowed to keep only one calculator on your desk. Make you pick! :)</p>
<p>^ I think they let you switch them. (e.g. you put one on the ground and switch when you need it).</p>