Reflection #2: Calculator Conundrums!

This week seems to have gone better for me. I am beginning to pick up concepts more quickly and easily. I am becoming much more accustomed and comfortable with using my calculator and it's various features. Word problems still give me trouble though, and I think my primary weakness is isolating data in problems, something that should go away with practice.

Anyway, I heard and saw that many of you have been having trouble with your calculators. Today I will be giving you a tutorial on how to find a minimum on a TI-Nspire equipped with a TI-84 Plus Keypad, however, the steps you see here will be identical for the TI-83 Plus, TI-83 Plus Silver Edition, TI-84 Plus, and TI-84 Plus Silver Edition.

We will be finding a Minimum of the equation: x(x+2)(x-2)(x-1)

1. Turn your calculator on if it isn't already. Duh!

2. Press the Key in the upper left corner labeled Y=

3. This is the screen you should get:

4. Enter your equation:

5. Press the GRAPH key in the upper left corner:

6. The calculator will graph the equation:

7.Get to the Calculate menu by pressing "2nd" followed by Trace:

Select minimum by scrolling to it using the directional pad and pressing enter. Alternatively, you can just press 3.

8. You should get to a screen that looks like this: (Note the Flashing Cursor)

9. Your minimum is somewhere in the bottom of this "valley".

10. Use the directional pad to move your cursor slightly to the left of the bottom of this "valley" and press enter.

11. Use the directional pad to move your cursor slightly to the right of the bottom of your "valley" and press enter again.

12. Your calculator will ask you whether you want it to guess the minimum between these points. Press enter to confirm.

13.Congratulations! You have found the first minimum for this equation.

Things to Remember:

* Each "valley" has a minimum, and each "peak" has a maximum.

** To find a maximum, use the same steps with these exceptions:

a. select "maximum" from the calculate menu

b. select the areas slightly left and right of each "peak".