Texas Instruments TI-89 Manuale Utente

Operating the Calculator

157

module. For example, it is important to know that functions such as x

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:

•

p · 7 = M63

– but –
9

p | 7 displays an error message.

•

| 2 = 4

– but –
6

· 2 =

M12 since it is interpreted as 6(M2), 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

)