538 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 538 of 132
xêCATALOG (^-1)
expression1 xê ⇒ expression
list1 xê ⇒ list
Returns the reciprocal of the argument.
For a list, returns the reciprocals of the
elements in list1.
3.1^ë1 ¸.322581
{a,4,ë.1,xì2}^ë1 ¸
{
1
a
1
4 ë10.
1
xì2}
squareMatrix1 xê ⇒ squareMatrix
Returns the inverse of squareMatrix1.
squareMatrix1 must be a non-singular square
matrix.
[1,2;3,4]^ë1 ¸
[1,2;a,4]^ë1 ¸
| (“with”) TI-89: Í key TI-92 Plus: 2 Í key
expression | Boolean expression1 [and Boolean
expression2]...[and Boolean expressionN]
The “with” (|) symbol serves as a binary
operator. The operand to the left of | is an
expression. The operand to the right of |
specifies one or more relations that are
intended to affect the simplification of the
expression. Multiple relations after | must be
joined by a logical “and”.
The “with” operator provides three basic
types of functionality: substitutions, interval
constraints, and exclusions.
x+1| x=3 ¸4
x+y| x=sin(y) ¸sin(y) + y
x+y| sin(y)=x ¸x + y
Substitutions are in the form of an equality,
such as x=3 or y=sin(x). To be most effective,
the left side should be a simple variable.
expression | variable = value will substitute
value for every occurrence of variable in
expression.
x^3ì2x+7!f(x) ¸Done
f(x)| x=‡(3) ¸‡3 + 7
(sin(x))^2+2sin(x)ì6
|
sin(x)=d
¸
dñ+2dì6
Interval constraints take the form of one or
more inequalities joined by logical “and”
operators. Interval constraints also permit
simplification that otherwise might be invalid
or not computable.
solve(x^2ì1=0,x)
|
x>0 and x<2
¸
x = 1
‡(x)ù‡(1/x)|x>0 ¸1
‡(x)ù‡(1/x) ¸1
x øx
Exclusions use the “not equals” (/= or ƒ)
relational operator to exclude a specific
value from consideration. They are used
primarily to exclude an exact solution when
using cSolve(), cZeros(), fMax(), fMin(), solve(),
zeros(), etc.
solve(x^2ì1=0,x)| xƒ1 ¸x = ë1