Texas Instruments TI-89 Voyage 200, User Manual

Page: 856 / 1008

856 Appendix A: Functions and Instructions
propFrac()
MATH/Algebra menu
propFrac(
expression1
[ ,
var
] )
⇒ ⇒ ⇒ ⇒
expression
propFrac(
rational_number
)
returns
rational_number
as the sum of an integer and a fraction having the
same sign and a greater denominator magnitude
than numerator magnitude.
propFrac(4/3)
¸
1 + 1/3
propFrac(
ë
4/3)
¸ ë
1
ì
1/3
propFrac(
rational_expression,var
)
returns the sum
of proper ratios and a polynomial with respect to
var . The degree of var in the denominator exceeds
the degree of var in the numerator in each proper
ratio. Similar powers of var are collected. The
terms and their factors are sorted with var as the
main variable.
If var is omitted, a proper fraction expansion is
done with respect to the most main variable. The
coefficients of the polynomial part are then made
proper with respect to their most main variable
first and so on.
For rational expressions,
propFrac()
is a faster
but less extreme alternative to
expand()
.
propFrac((x^2+x+1)/(x+1)+
(y^2+y+1)/(y+1),x)
¸
propFrac(ans(1))
PtChg
CATALOG
PtChg
x
,
y
PtChg
xList
,
yList
Displays the Graph screen and reverses the screen
pixel nearest to window coordinates
(
x
,
y
).
Note:
PtChg
through
PtText
show continuing
similar examples.
PtChg 2,4
¸
PtOff
CATALOG
PtOff
x
,
y
PtOff
xList
,
yList
Displays the Graph screen and turns off the
screen pixel nearest to window coordinates
(
x
,
y
).
PtOff 2,4
¸
PtOn
CATALOG
PtOn
x
,
y
PtOn
xList
,
yList
Displays the Graph screen and turns on the screen
pixel nearest to window coordinates
(
x
,
y
).
PtOn 3,5
¸
ptTest()
CATALOG
ptTest (
x
,
y
)
⇒
⇒ ⇒
⇒
Boolean constant expression
ptTest (
xList
,
yList
)
⇒
⇒ ⇒
⇒
Boolean constant expression
Returns
true
or
false
. Returns
true
only if the
screen pixel nearest to window coordinates ( x , y )
is on.
ptTest(3,5)
¸
true