Texas Instruments TI-92 Getting Started page 8

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Graphing Technology Guide: TI-92
Figure 5.11: Y= screen Figure 5.12: Evaluating a function
Assign the value 2230 to the variable x by these keystrokes: 2230 STO➧ X ENTER. Then press the following
keystrokes to evaluate y1 and find January's wages: Y 1 ( X ) ENTER, completes the calculation. It is not
necessary to repeat all these steps to find the February wages. Simply press to begin editing the previous entry,
change X to 1865, and press ENTER (see Figure 5.12).
You may also have the TI-92 make a table of values for the function. Press TblSet to set up the table (Figure
5.13). Move the blinking cursor down to the fourth line beside Independent:, then press and 2[ASK] ENTER.
This configuration permits you to input values for x one at a time. Now press TABLE or APPS 5[Table], enter
2230 in the x column, and press ENTER (see Figure 5.14). Press to move to the next line and continue to enter
additional values for x. The TI-92 automatically completes the table with the corresponding values of y1. Press 2nd
QUIT to leave the TABLE screen.
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Technology Tip: The TI-92 requires multiplication to be expressed between variables, so xxx does not mean x ,
rather it is a new variable named xxx. Thus, you must use either ×'s between the x's or ∧ for powers of x. Of course,
expressed multiplication is not required between a constant and a variable. See your TI-92 manual for more
information about the allowed usage of implied multiplication.
Figure 5.13: Table Setup screen Figure 5.14: Table of values
5.2.2 Functions in a Graph Window: Once you have entered a function in the Y= screen of the TI-92, just press
GRAPH to see its graph. The ability to draw a graph contributes substantially to our ability to solve problems.
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Y= and delete anything that may be there by moving
For example, here is how to graph y = –x + 4x. First press
with the arrow keys to y1 or to any of the other lines and pressing CLEAR wherever necessary. Then, with the
cursor on the (now cleared) top line (y1), press (-) X ∧ 3 + 4 X ENTER to enter the function (as in Figure 5.15).
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GRAPH and the TI-92 changes to a window with the graph of y = –x
Now press +4x. While the TI-92 is
calculating coordinates for a plot, it displays a the word BUSY on the status line.
Technology Tip: If you would like to see a function in the Y= menu and its graph in a graph window, both at the
same time, press MODE to open the MODE menu and press F2 to go to the second page. The cursor will be next to
Split Screen. Select either TOP-BOTTOM or LEFT-RIGHT by pressing and 2 or 3, respectively. Now the 2
lines below the Split 1 App line have become readable, since these options apply only when the calculator is in the
split screen mode. The Split 1 App will automatically be the screen you were on prior to pressing MODE. You can
choose what you want the top or left-hand screen to show by moving down to the Split 1 App line, pressing
and
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