EL-9600/9400 Graphing Calculator
Notes
Step & Key Operation
(When using EL-9600)
*Use either pen touch or cursor to operate.
Display
(When using EL-9600)
8-4
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2
-
1
Enter the function
y =
|3.5
x
+ 4|for Y1.
Enter
y =
10 for Y2.
*
*
*
2
-
2
*
*
*
*
*
Since the inequality you are
solving is Y1 > Y2, the solu-
tion is where the graph of Y2
is “on the bottom” and Y1 in
“on the top.”
Set up shading.
2
-
3
Choose viewing windows “-10 <
x
<
10,” and “-5 <
y
< 50” using Rapid
Window feature and view the graph.
*
*
*
2
-
4
*
➞
x
= -4,
y
= 10
*
➞
x
= 1.714285714
y
= 9.999999999 ( Note)
The intersections are (-4, 10)
and (1.7, 10.0). The solution
is all values of
x
such that
x
<
-
4 or
x
>1.7.
( Note: The value of
y
in the
intersection of the two graphs
may not appear exactly as 10
as shown in the example, due
to an error caused by approxi-
mate calculation.)
Find the points of intersection.
Solve the inequality.
The EL-9600/9400 shows absolute values with | | just as written on paper by
using the Equation editor. Graphical solution methods not only offer instructive
visualization of the solution process, but they can be applied to inequalities that
are often difficult to solve algebraically. The Shade feature is useful to solve the
inequality visually and the points of intersection can be obtained easily.
Y=
CL
MATH
+
2nd F
DRAW
2nd F
2nd F
CALC
CALC
EZ
WINDOW
ENTER
ENTER
ENTER
ENTER
—
—
—
1
0
B
1
3
5
4
G
1
5
2
2
2
3
•
X
/
/
T
/
n
HB1.DocD.
98.10.1, 6:11 PM
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