Texas Instruments TITANIUM TI-89 - Manual (Page 200)

Operating the Calculator 200
Displaying a Variable Displaying a Variable Displaying a Variable Displaying a Variable
If the variable is undefined, the variable name is shown in the result.
Using a Variable in an Expression Using a Variable in an Expression Using a Variable in an Expression Using a Variable in an Expression
1. Type the variable name.
2. Press ¸.
In this example, the variable a is undefined.
Therefore, it is used as a symbolic variable.
Note: Refer to Symbolic Manipulation for
information about symbolic manipulation.
1. Type the variable name into the
expression.
2. Press ¸ to evaluate the expression.
Note: To view a list of existing variable
names, use 2 ° as described in
Memory and Variable Management.
If you want the result to replace the variable’s
previous value, you must store the result.
The variable’s value
did not change.