Texas Instruments Titanium TI-89, User Manual

Page: 148 / 977

Operating the Calculator 145
module. For example, it is important to know that functions such as x
2
are evaluated
before negation.
If you use
|
instead of
·
(or vice versa), you may get an error message or you may get
unexpected results. For example:
• 9
p ·
7 =
M
63
– but –
9
p |
7 displays an error message.
• 6
|
2 = 4
– but –
6
·
2 =
M
12 since it is interpreted as 6(
M
2), implied multiplication.
•
·
2
«
4 = 2
– but –
|
2
«
4 subtracts 2 from the previous answer and then adds 4.
Important:
Use
|
for subtraction and use
·
for negation.
Entering a Number in Scientific Notation
1. Type the part of the number that precedes the exponent. This value can be an
expression.
Use
c
and
d
to include parentheses if you
have any doubt about how a negation will be
evaluated.
Evaluated as M (2
2
)