Calculator User Manual

460 Appendix A: Functions and Instructions
8992APPA.DOC TI-89 / TI-92 Plus: Appendix A (US English) Susan Gullord Revised: 02/23/01 1:48 PM Printed: 02/23/01 2:21 PM Page 460 of 132
lcm()
MATH/Number menu
lcm(
number1
,
number2
)
⇒
expression
lcm(
list1
,
list2
)
⇒
list
lcm(
matrix1
,
matrix2
)
⇒
matrix
Returns the least common multiple of the
two arguments. The
lcm
of two fractions is
the
lcm
of their numerators divided by the
gcd
of their denominators. The
lcm
of
fractional floating-point numbers is their
product.
For two lists or matrices, returns the least
common multiples of the corresponding
elements.
lcm(6,9)
¸
18
lcm({1/3,
ë
14,16},{2/15,7,5})
¸
{2/3 14 80}
left()
MATH/String menu
left(
sourceString
[
,
num
]
)
⇒
string
Returns the leftmost
num
characters
contained in character string
sourceString
.
If you omit
num
, returns all of
sourceString
.
left("Hello",2)
¸
"He"
left(
list1
[
,
num
]
)
⇒
list
Returns the leftmost
num
elements contained
in
list1
.
If you omit
num
, returns all of
list1
.
left({1,3,
ë
2,4},3)
¸
{1 3
ë
2}
left(
comparison
)
⇒
expression
Returns the left-hand side of an equation or
inequality.
left(x<3)
¸
x
limit()
MATH/Calculus menu
limit(
expression1
,
var
,
point
[
,
direction
]
)
⇒
expression
limit(
list1
,
var
,
point
[
,
direction
]
)
⇒
list
limit(
matrix1
,
var
,
point
[
,
direction
]
)
⇒
matrix
Returns the limit requested.
direction
: negative=from left, positive=from
right, otherwise=both. (If omitted,
direction
defaults to both.)
limit(2x+3,x,5)
¸
13
limit(1/x,x,0,1)
¸
ˆ
limit(sin(x)/x,x,0)
¸
1
limit((sin(x+h)-sin(x))/h,h,0)
¸
cos(x)
limit((1+1/n)^n,n,ˆ)
¸
e
Limits at positive
ˆ
and at negative
ˆ
are
always converted to one-sided limits from the
finite side.
Depending on the circumstances,
limit()
returns itself or
undef
when it cannot
determine a unique limit. This does not
necessarily mean that a unique limit does not
exist.
undef
means that the result is either an
unknown number with finite or infinite
magnitude, or it is the entire set of such
numbers.