Texas Instruments TI-89 Manual Book page 465

factor(rationalNumber)
number factored into primes. For composite
numbers, the computing time grows
exponentially with the number of digits in the
second-largest factor. For example, factoring
a 30-digit integer could take more than a day,
and factoring a 100-digit number could take
more than a century.
Note: To stop (break) a computation, press
´.
If you merely want to determine if a number
is prime, use
faster, particularly if
prime and if the second-largest factor has
more than five digits.
Fill
MATH/Matrix menu
Fill expression, matrixVar
Replaces each element in variable
with
expression
matrixVar
Fill expression, listVar
Replaces each element in variable
with
expression
must already exist.
listVar
floor()
MATH/Number menu
floor(expression)
Returns the greatest integer that is  the
argument. This function is identical to
The argument can be a real or a complex
number.
floor(list1)
floor(matrix1)
Returns a list or matrix of the floor of each
element.
Note: See also
fMax()
MATH/Calculus menu
fMax(expression, var)
Returns a Boolean expression specifying
candidate values of
expression
448 Appendix A: Functions and Instructions
returns the rational
instead. It is much
isPrime()
rationalNumber
matrix
.
must already exist.
list
.
integer
list
matrix
and .
ceiling() int()
Boolean expression
that maximize
var
or locate its least upper bound.
factor(152417172689) ¸
isPrime(152417172689) ¸false
is not
[1,2;3,4]! amatrx ¸
Fill 1.01,amatrx ¸
matrixVar
amatrx ¸
{1,2,3,4,5}! alist ¸
listVar
Fill 1.01,alist ¸
alist ¸
{1.01 1.01 1.01 1.01 1.01}
floor(ë 2.14) ¸
.
int()
floor({3/2,0,ë 5.3}) ¸
floor([1.2,3.4;2.5,4.8]) ¸
fMax(1ì (xì a)^2ì (xì b)^2,x) ¸
fMax(.5x^3ì xì 2,x) ¸
123457ø1234577
1 2
[ ]
3 4
Done
1.01 1.01
[ ]
1.01 1.01
{1 2 3 4 5}
Done
ë 3.
{1 0 ë 6.}
1. 3.
[ ]
2. 4.
a+b
x =
2
x = ˆ