In order to see the effects of a ZOOM option, a graph must already be displayed on the screen. To learn how to enter and graph a function, go to Graphing a Function . For example, the function = is graphed below.
The ZOOM 3:Zoom Out option allows the user to select a new VIEWING RECTANGLE around a given point that is larger than the existing VIEWING RECTANGLE. Both the Zoom In and Zoom Out results depend on the ZOOM FACTORS.
To select the ZOOM 3:Zoom Out option, first press the ZOOM key and then select 3.
Note: The X and Y coordinates may vary depending on what was last done on the calculator. Whatever X and Y are displayed on the screen will remain in the center of the image.
Now press the ENTER key. The VIEWING RECTANGLE will remain centered around the X and Y listed at the bottom of the screen, but the size of the VIEWING RECTANGLE will be 4 times of its orginal size (assuming Xfact and Yfact are both 4). Thus, the standard VIEWING RECTANGLE of [-10, 10, 1] X [-10,10,1] is now [-40,40,1] X [-40,40,1]. See the result below.
Note that because there are so many tick marks with Xscl and Yscl both set at 1, they blend into a line. Pressing the ENTER key again will give a graph similar to the one shown below. The new VIEWING RECTANGLE is [-160,160,1] X [-160,160,1] . The given function is hardly visible. Zoom Out can reverse a Zoom In operation.
The Zoom Out operations may also be centered on a point See Zoom In to see how this is done.
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