Owner's Manual

902 Appendix A: Functions and Instructions
!
(factorial)
@ ¥ e key H 2 W key
expression1 ! ⇒
⇒⇒
⇒ expression
list1 ! ⇒
⇒⇒
⇒ list
matrix1 ! ⇒
⇒⇒
⇒ matrix
Returns the factorial of the argument.
For a list or matrix, returns a list or matrix of
factorials of the elements.
The TI-89 computes a numeric value for only
non-negative whole-number values.
5! ¸ 120
{5,4,3}! ¸ {120 24 6}
[1,2;3,4]! ¸ [
1 2
6 24
]
&
(append)
@ ¥ p key H 2 H key
string1 & string2 ⇒
⇒⇒
⇒ string
Returns a text string that is string2 appended to
string1 .
"Hello " & "Nick" ¸
"Hello Nick"
‰()
(integrate)
2<key
‰( expression1 , var [, lower ] [, upper ]) ⇒
⇒⇒
⇒ expression
‰( list1,var [, order ]) ⇒
⇒⇒
⇒ list
‰(
matrix1,var [, order ]) ⇒
⇒⇒
⇒ matrix
Returns the integral of expression1 with respect to
the variable
var from lower to upper .
‰(x^2,x,a,b) ¸
bò
3
-
aò
3
Returns an anti-derivative if lower and upper are
omitted. A symbolic constant of integration such
as
C is omitted.
However,
lower is added as a constant of
integration if only
upper is omitted.
‰(x^2,x) ¸
xò
3
‰(aù x^2,x,c) ¸
aø xò
3
+ c
Equally valid anti-derivatives might differ by a
numeric constant. Such a constant might be
disguised—particularly when an anti-derivative
contains logarithms or inverse trigonometric
functions. Moreover, piecewise constant
expressions are sometimes added to make an
anti-derivative valid over a larger interval than
the usual formula.
‰(1/(2ì cos(x)),x)! tmp(x) ¸
ClrGraph:Graph tmp(x):Graph
1/(2ì cos(x)):Graph ‡(3)
(2tanê (‡(3)(tan(x/2)))/3)
¸
‰() returns itself for pieces of expression1 that it
cannot determine as an explicit finite
combination of its built-in functions and
operators.
When
lower and upper are both present, an
attempt is made to locate any discontinuities or
discontinuous derivatives in the interval
lower <
var < upper
and to subdivide the interval at those
places.
‰(bù e ^(ë x^2)+a/(x^2+a^2),x)
¸