3-8-6

Analyzing a Function Used to Draw a Graph

STo determine the definite integral for a particular domain

Example: To graph the function y = x(x + 2)(x – 2) and obtain its definite integral in the domain of 1 x 2

(1)Display the View Window dialog box, and then configure it with the following parameters.

xmin = –7.7,

xmax = 7.7,

xscale = 1

ymin = –4,ymax = 4,

yscale = 1

(2)On the Graph Editor window, input and store y = x(x + 2)(x – 2) into line y1, and then tap to graph it.

Make sure that only y1 is checked.

(3)Tap [Analysis], [G-Solve], and then [ ° dx].This displays “Lower” on the Graph window.

(4) Press

.

This displays a dialog box for inputting an interval for the x-values, with 1 specified for the lower limit of the x-axis (Lower).

(5)Tap the [Upper] input box and then input 2 for the upper limit of the x-axis.

(6)Tap [OK].

Tip

Instead of inputting [Lower] and [Upper] values in steps (4) through (6), you can use the cursor key or the graph controller arrows to move the pointer along the graph to specify the lower limit and upper limit. If you do, perform the following two steps after step (3).

(4)Use the cursor key or the graph controller to move the pointer to the location of the lower limit and then press .

This registers the lower limit and changes the word in the lower right corner of the Graph window to “Upper”.

(5)Move the pointer to the location of the upper limit, and then press .

Result Screenshot

20060301