Texas Instruments Titanium TI-89, Руководство пользователя

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Appendix A: Functions and Instructions 829
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