Calculator User Manual

294
Chapter 20: A to Z Function and Instruction Reference
20ATOZ.DOC TI-86, Chap 20, US English Bob Fedorisko Revised: 02/13/01 2:42 PM Printed: 02/13/01 3:05 PM Page 294 of 118
ExpR
Uses
xStat
,
yStat
, and
fStat
, and stores the regression
equation to
RegEq
only.
Factorial:
!
MATH PROB menu
number !
or
(expression) !
Returns the factorial of a real integer or non-integer,
where 0

integer

449 and 0

non-integer

449.9. For
a non-integer, the Gamma function is used to find the
factorial. An
expression
must evaluate to an appropriate
value.
6!
b
720
12.5!
b
1710542068.32
list !
Returns a list in which each element is the factorial of
the corresponding element in
list
.
{6,7,8}!
b
{720 5040 40320}
fcstx
† STAT menu
fcstx yValue
Based on the current regression equation (
ReqEq
),
returns the forecasted
x
at a real
yValue
.
fcsty
† STAT menu
fcsty xValue
Based on the current regression equation (
ReqEq
),
returns the forecasted
y
at a real
xValue
.