48 Chapter 2: Operating the Calculator
02OPER.DOC TI
-
89/TI
-
92Plus: O
p
eratingthe TI
-
89/TI
-
92Plus (English) SusanGullord Revised:02/23/01 1:06 PM Printed:02/23/01 2:11 PM Page48 of 44
1. Enter the value you want to store, which can be an expression.
2. Press §. The store symbol (!) is displayed.
3. Type the variable name.
4. Press ¸.
To store to a variable temporarily, you can use the “with” operator.
Refer to “Substituting Values and Setting Constraints” in Chapter 3.
1. Type the variable name.
2. Press ¸.
If the variable is undefined, the variable name is shown in the result.
In this example, the variable a is
undefined. Therefore, it is used as a
symbolic variable.
1. Type the variable name into the
expression.
2. Press ¸ to evaluate the
expression.
If you want the result to replace the
v
ariable’s previous value, you must
store the result.
In some cases, you may want to use a variable’s actual value in an
expression instead of the variable name.
1. Press 2£to display a dialog
box.
2. Type the variable name.
3. Press ¸ twice.
In this example, the value stored in num1 will be inserted at the
cursor position in the entry line.
Storing a Value in a
Variable
Note:
TI-89
users should
use
j
as necessary
when typing variable names.
Displaying a
Variable
Note: Refer to Chapter 3 for
information about symbolic
manipulation.
Using a Variable in
an Expression
Tip: To view a list of existin
g
variable names, use
2°
as described in
Chapter 21.
Recalling a
Variable’s Value
The variable’s value
did not change.