B. Examples1. Polynomial Functions

Example: Graph the function shown in the first window below. Use both ZoomDec and ZoomStd windows.

Press

select y1, type the

function and . Press and to

select ZoomDec. Press to graph. Press and to

draw the graph

in ZoomStd.You can see that either one of these windows is good enough to use. However, the ZoomDec window would probably be the better one to use.

Example: Graph the function shown in the first window below. Use both ZoomDec and ZoomStd windows.

Enter the function. Using ZoomDec. Using ZoomStd.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.

Table Values Set a Window

Graph the function.