Texas Instruments TITANIUM TI-89 - Manual (Page 160)

Operating the Calculator 160
• This guidebook uses the word command as a generic reference to both functions
and instructions.
Implied Multiplication Implied Multiplication Implied Multiplication Implied Multiplication
The graphing calculator recognizes implied multiplication, provided it does not conflict
with a reserved notation.
Parentheses Parentheses Parentheses Parentheses
Expressions are evaluated according to the Equation Operating System (EOS™)
hierarchy described in the Technical Reference module. To change the order of
evaluation or just to ensure that an expression is evaluated in the order you require, use
parentheses.
Calculations inside a pair of parentheses are completed first. For example, in 4(1+2),
EOS first evaluates (1+2) and then multiplies the answer by 4.
If you enter: The calculator interprets it as:
Valid 2 p
4 sin(46)
5(1+2) or (1+2)5
[1,2]a
2(a)
2
щp
4
щ
sin(46)
5
ù
(1+2) or (1+2)
ù
5
[a 2a]
2
ù
a
Invalid xy
a(2)
a[1,2] Single variable named xy
Function call
Matrix index to element a[1,2]