20060301
3-8-8
Analyzing a Function Used to Draw a Graph
(2) On the Graph Editor window, input and store
y
1 =
x
3
– 1 into line
y
1, and then tap
$
to graph it.
• Make sure that only “
y
1” is selected (checked).
(3) Tap [Analysis], [G-Solve], and then [Inflection].
• This causes “Inflection” to appear on the Graph window, with a pointer located at the
point of inflection.
Tip
• If your function has multiple inflection points, use the cursor button or graph controller arrows to
move the pointer between them and display their coordinates.
u
To obtain the volume of a solid of revolution
Example: To graph the function
y
=
x
2
–
x
– 2 and obtain the volume of a solid of revolution
as the line segment from
x
= 1 to
x
= 2 is rotated on the
x
-axis
(1) Display the View Window dialog box, and then configure it with the following parameters.
xmin = –7.7, xmax = 7.7, xscale = 1
ymin = –3.8, ymax = 3.8, yscale = 1
(2) On the Graph Editor window, input and store
y
=
x
2
–
x
– 2 into line
y
1, and then tap
$
to graph it.
• Make sure that only
y
1 is checked.
(3) Tap [Analysis], [G-Solve], and then [
π
∫
(
f
(
x
))
2
dx
].
• This displays a crosshair pointer on the graph, and the word “Lower” in the lower right
corner of the Graph window.