II. Setting a Window - Finding One That Works

B. Examples

1. Polynomial Function Examples

For these examples, we will use several of the techniques covered in part A of this module.

i) Example 1: Graph the function . For this function we will use the ZDECM and ZSTD windows.

Enter the function by pressing and .

Enter the function.
to get to ZOOM.
Press for ZSTD.
for ZDECM.

You can see that either one of these windows is good enough to use. However, the ZDECM window is the better one to use since it is a friendly window and the TRACE will move in increments of 0.1.

ii) Example 2: Graph the function using ZDECM and ZSTD.

Enter the function.
Using ZDECM..
Using ZSTD.

Since these windows do not give a good graph, use the TABLE to find the window. Notice in the graphs above that the function crosses the x-axis between -2 and -1 and around 5. Access the TABLE window and enter several values of X between-4 and 8 to determine the appropriate Y values. Once you have a good idea of the values of the function, set the window to fit the graph. You may need to try more than one window to get a good picture, but the TABLE will help you find a good starting point. To get rid of the menu bar across the bottom of a screen press .

TABLE Values
Set a Window