Texas Instruments TI-89 Manual page 29

TI-89 Guide
Press
F1 (Y
screen has a check mark to the left of the name. This tells you
that is turned on and ready to be graphed. You can also see
Plot1
the settings you chose for the plot.
•
A scatter plot is turned on when there is a check mark to the left of its name on the
screen. From now on, you can turn the scatter plot off and on by having
checked or not checked. To turn
Reverse the process to turn
•
TI-89 data lists can be named and stored in the calculator's memory for later recall and use.
Refer to Section 1.5.13 and 1.5.14 of this Guide for instructions on storing data lists and
later recalling them for use.
1.5.6 DRAWI NG A SCATTER PLOT OF DATA Any functions that are turned on in the
will graph when you plot data. Therefore, you should clear or turn them off before you draw a
scatter plot. We illustrate how to graph data using the modified tax data that follows Example
2 in Section 1.5 of Calculus Concepts.
Year
Tax (in dollars)
Access the graphing list. If any entered function is no longer needed, clear it by pressing
Y=
If you want the function(s) to remain but not graph when you draw the scatter plot,
CLEAR .
remove the check mark next to that function with
the screen is turned on (i.e., checked).
Y=
Access the data with
Using the table given above, enter the year data in
[Current].
and the modified tax data in
given in Section 1.5.1 of this Guide.
(You can either leave values in the other lists or clear them.)
Press
F1 (Y
the calculator set an autoscaled view of the data and draw the
scatter plot. (Note that
tick marks.)
Recall that if the data are perfectly linear (that is, every data point falls on the graph of a line),
the first differences in the output values are constant. The first differences for the original tax
data were constant at $541, so a linear function fit the data perfectly. What information is
given by the first differences for these modified tax data?
Run program
DIFF.
of this Guide.) Recall that the program
stores the first differences in list
you want to recall them on the home
screen.
Copyright © Houghton Mifflin Company. All rights reserved.
and Notice that
) ▲ .
=
off, press
Plot1
back on.
Plot1
1996 1997
2541 3081
APPS 6 [Data/Matrix Editor]
according to the instructions
c2
and then
) F2 [Zoom] 9 [ZoomData]
=
also resets the x- and y-axis
ZoomData
(See Section 1.5.4
if
d1
at the top of the
Plot1
to remove the check mark.
F4 [ ]
b
1998 1999
3615 4157
Also be sure that
F4 [ ] .
b
and choose
1
c1
to have
TI 89-29
Y=
either
Plot1
list
Y=
2000 2001
4703 5242
at the top of
Plot 1