EL-9600/9400 Graphing Calculator
9-2
There may be differences in the results of calculations and graph plotting depending on the setting.
Return all settings to the default value or to delete all data.
Set the zoom to the decimal window:
*
(
*
)
*
Before
Start
Notes
Step & Key Operation
(When using EL-9600)
*Use either pen touch or cursor to operate.
Display
(When using EL-9600)
Solving Rational Function Inequalities
A rational function
f
(
x
)
is defined as the quotient
where
p
(
x
)
and
q
(
x
)
are two
polynomial function such that
q
(
x
)
≠
0.
The solutions to a rational function inequality can
be obtained graphically using the same method as for normal inequalities. You can find the
solutions by graphing each side of the inequalities as an individual function.
Solve a rational inequality.
Example
Solve
≤
2 by graphing each side of the inequality as an individual function.
*
*
*
*
1
Enter
y =
for Y1. Enter
y =
2
for Y2.
2
Set up the shading.
Since Y1 is the value “on the
bottom” (the smaller of the
two) and Y2 is the function
“on the top” (the larger of the
two), Y1 < Y < Y2.
*
*
*
*
3
View the graph.
4
Find the intersections, and solve the
inequality.
The intersections are when
x
= -1.3, -0.8, 0.8, and 1.3.
The solution is all values of
x
such that
x
≤
-1.3 or
-0.8
≤
x
≤
0.8 or
x
≥
1.3.
*
Do this four times
○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
The EL-9600/9400 allows the solution region of inequalities to be indicated
visually using the Shade feature. Also, the points of intersections can be obtained
easily.
x
1
- x
2
x
1-
x
2
Y=
ENTER
a/b
A
ZOOM
MATH
7
B
1
1
2
G
1
2
GRAPH
2nd F CALC
2nd F DRAW
—
ALPHA
x
2
ENTER
—
—
—
X
/
/
T
/
n
X
/
/
T
/
n
q
(
x
)
p
(
x
)
HB1.DocD.
98.10.1, 6:13 PM
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