20 Getting Started with TI InterActive!
TII_GettingStarted.doc Getting Started with TI InterActive! Karen Davis Revised: 8/22/03 12:20 PM Printed: 8/25/03 8:04 AM Page 20 of 64
After storing a value in a variable, you can use the variable name
in an expression as a substitute for the stored value.
1. Click the Math Box button
to insert a new Math Box, if
necessary.
2. Type
4*25*num^2
in the Math Box, and press Enter.
TI InterActive! substitutes 517, the value assigned to
num
, and
evaluates the expression.
3. Type
4*25*nonum^2
in a Math Box, and press Enter.
Because the variable
nonum
has not been defined, it is treated
algebraically in the result.
If you want to update a variable with the result of a calculation,
you must store the result explicitly.
Entry Result
Comment
a := 2
2
a^3
8
Result not stored in variable
a
.
a
2
a := a^3
8
Variable
a
updated with result.
a
8
a^2
N
> a
64
Variable
a
updated with result.
a
64
Using a variable
in a calculation
Updating a
variable
