TI89-26
Chapt er 1
Copyright © Houghton Mifflin Company. All rights reserved.
The results of our numerical and graphical investigations are confirmed by the algebraic
answers. Note that the TI-89 prints
undef
to mean undefined or does not exist.
1.5 Linear Functions and Models
This portion of the Guide gives instructions for entering real-world data into the calculator and
finding familiar function curves to fit that data. You will use the beginning material in this
section throughout all the chapters in Calculus Concepts.
CAUTI ON:
You need to name the data variable in the TI-89, and you are instructed below to
use the name
calcc
. Do not change or vary this name. If you do, the programs that you use
later will not properly execute. Also, be careful when you enter data in the TI-89 because the
model and all results depend on the values that are entered! Always check your entries.
1.5.1 ENTERING DATA We illustrate data entry using the values in Table 1.46 in Section 1.5.
Year 1996 1997 1998 1999 2000 2001
Tax (in dollars) 2532 3073 3614 4155 4696 5237
Before beginning, clear out previous work with
HOME 2nd F1 [F6] 2 [NewProb] ENTER .
Press
APPS 6 [Data/Matrix Editor] and choose 3 [New].
Choose
the settings shown to the right for the first two positions. Name
thevariablebypressing
2nd alpha (a-lock)
and type
calcc.
(
We use this variable name for all data in this Guide.Seethe
CAUTION
note above.)
Press
ENTER
until you see the screen
shown to the right. These are the lists
that hold data. You can access many
other lists by highlighting the list name
and using
►
.
In this Guide, we usually use list
c1
for the input data and list
c2
for the output data. If there are
any data values already in your lists, see Section 1.5.3 of this Guide and first delete any “old”
data. To enter data in the lists, do the following:
Position the cursor in the first location in list
c1
. Enter the input
data into list
c1
by typing the years from top to bottom in the
c1
column, pressing
ENTER
or
▼
after each entry. (If a letter
rather than a number prints, alpha-lock is still on. Press
alpha
to
release it.) Use the shortcut in the
NOTE
below to enter the tax
values in
c2
.
NOTE: After typing the sixth input value, 2001, use
▲
to have the cursor go to the top
of list
c1
andthenpress
►
to be in the first row of the
c2
column. Enter the output data into
list
c2
by typing the entries from top to bottom in the
c2
column, pressing
ENTER
or
▼
after
each tax value. (
▼
causes the cursor to jump to the bottom of the current column. See
page 232 of the TI-89 Guidebook for other key combinations that scroll the data lists.)