3-8-3

Analyzing a Function Used to Draw a Graph

u To obtain the minimum value, maximum value, y-intercept, and inflection of a function

Example: To graph the function y = 1 x2(x + 2)(x – 2) and obtain its minimum value 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 = –3.8,

ymax = 3.8,

yscale = 1

(2)On the Graph Editor window, input and store y = then tap $ to graph it.

• Make sure that only y1 is checked.

1x2 (x + 2)(x – 2) into line y1, and

(3)Tap [Analysis], [G-Solve], and then [Min], or tap I.

•This displays “Min” on the Graph window, and locates a pointer at the first solution of the minimum value (minimum value of y for smallest value of x). The x- and y-coordinates at the current pointer location are also shown on the Graph window.

(4)To obtain other minimum values, press the left or right cursor key, or tap the left or right graph controller arrows.

•If there is only one solution, the pointer does not move when you press the cursor key.

Result Screenshots

Tip

•To obtain the other values, select the applicable command on the [G-Solve] menu in step (3) of the above procedure.

To obtain this value:

Select this G-Solve menu command:

Maximum value

Max (or tap U)

y-intercept

y-Intercept

Point of inflection

Inflection

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