1. A useful tool.

2.  (Formerly) tiny computers – you can even program them.  TI-83+, TI-84+, TI-89 are the ones with which I am most familiar.  There are others, but Texas Instruments (TI) has a bit of a chokehold on the industry (or at least that’s what the $90 price on the TI-83+ seems to indicate).  Can’t I just use my cell phone/an app?  Not on the SAT, ACT, or college, ever.

3.  Parenthesis! This thing always follows order of operations.  Put that in your calculator. What do you get?  You can go back and modify what you typed by using “2 nd “+ “ENTER” (which is “ENTRY”) and put things in using “2 nd ” + “DEL” (which is “INS”) – it pushes the thing it’s on to the right.

4.  If your science teacher gives you a problem that leads into the next problem, or a lab whose work builds on itself, use “2 nd ” + “(-)” (“ANS”) and the Ans that appears on the screen will use whatever answer value appeared most recently.  This also means if you screw it up you have to redo the first step, because it will keep using the most recent answer  Type in “Ans + 2” and press Enter a few times.

5.  Common functions – squaring, square roots, sin/cos/tan, log, ln, π, e, these are all available on buttons.  “MATH” button includes most of everything else you could need.  Try putting in

6.  The thing you’ll use the most here is  Radian Degrees  This determines what units it thinks you’re using for trig.  Highlight radians, then type in sin( π )  Highlight degrees, then type in sin( π )

7.  Y=  X, T, θ, n x2x2  GRAPH  “2 nd ” + “GRAPH” = “TABLE”  You can view a T-chart here

8.  WINDOW lets you define the edges of the screen  ZOOM lets you generically zoom in or out – if you aren’t sure how far off your window is  “2 nd ” + “TRACE” = “CALC”  This lets you do graph-calculations, like find roots, maximums and minimums, derivatives, and integrals

9.  Built-in solver  “MATH”  Option “0”  If you have a single-variable equation and set it equal to zero, your calculator will solve it.  WARNINGS  It only gives you one answer  It iterates, so sometimes it gives decimal

10.  Try x 2 – x + 20 = 0  (You have to use “ALPHA” + “ENTER” = “SOLVE”)  What answer did you get?  The number that’s in the X= spot is where it starts.  Try 4  Now try 6

11.  You can write a short program that will perform the quadratic formula for you.  http://math.arizona.edu/~krawczyk/Calculat or/TI83PLUS/TI83PQF.html http://math.arizona.edu/~krawczyk/Calculat or/TI83PLUS/TI83PQF.html  It won’t give you imaginary answers – you could program a bunch more in to make it look like it did that, but the calculator is not equipped to actually deal with imaginary values.