Graph; Cursor - Texas Instruments TI-82 Keystroke Manual

you get a better look at this free-moving cursor. This cursor should be moved to approximately
the coordinates of the point you want to have in the center of the screen after the calculator creates
the Integer graphing window. If you wish to have the point (7,5) at the center of the Integer
graphing window, then move this free-moving cursor to a point as close to (7,5) as possible. That
is, move the cursor with the arrow keys until the coordinates displayed at the bottom of the screen
are as close as you can get them to x = 7 and y = 5. (From the Standard graphing window, the
closest you can come is probably x = 7.0212766 and y = 4.8387097.) Press ENTER to produce the
Integer graphing window centered at (7,5). Press the Right Arrow key to produce a larger free-
moving cursor one pixel to the right of the center of the screen. (See 19 Cursor for more details
about this cursor.) Note that the coordinates of the cursor are (8,5). Press the Left Arrow key to
return to the center of the screen, which is at (7,5). Press other arrow keys and note that every
time you press the Left Arrow key or the Right Arrow key, the value of x remains an integer and
changes by 1. Likewise, every time you press the Down Arrow key or the Up Arrow key, the
value of y remains an integer and changes by 1. You may want to look at the Window settings to
see how things have been changed.
Press the GRAPH key again to display the graphing window. If you want to change the
coordinates of the center to some other point, such as the origin (0,0), press ZOOM 8, move the
cursor to (0,0), and press ENTER. A new Integer graphing window will be produced, this time
centered at the origin. Use the arrow keys to verify that this change has taken place.
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18 Graph

See 16 Window and Default first to learn how to set the left, right, bottom, and top of the
graphing window with the Window settings. To see the graphing window you have selected, press
GRAPH.
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19 Cursor

Press the GRAPH key to display the graphing window. (It doesn't matter which graphing window
you are using, nor does it matter if graphs are displayed.) Press one of the arrow keys. (It doesn't
matter which one.) You will notice that near the center of the screen there is a cross hair, and at
the bottom of the screen there are values for x and y which represent the coordinates of the cross
hair. If you cannot see the cross hair clearly because it lies on one of the axes, press the Up Arrow
key a few times and the Right Arrow key a few times to get the cross hair away from the axes.
You may notice that when you do this, the coordinates displayed at the bottom of the screen
change to reflect the changed position of the cross hair. This cross hair may be moved to any part
of the graphing window by using the arrow keys. The cross hair is sometimes called the general
cursor or free-moving cursor. To turn this general cursor off, just press the GRAPH key.
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