# Popp

## Popp

Graphing functions using the TI-84 Plus

We present instructions for graphing functions using the TI-84 Plus calculator (similar instructions apply to other calculators).

In general, there are 4 steps:
1. Enter the formula for the function you wish to graph using the Y= editor.
2. Set the viewing window.
3. Graph the function.
4. Adjust the viewing window, if necessary.

Example. Graph the function f where[pic] The 4 general steps become:

Step 1. Press [Y=] to display the Y= editor. Type the formula for f as shown in Figure 1. Make sure to use the “variable” key [[pic]] when entering the variable x.

Step 2. On the first try to graph this function, we will accept the default standard window, so we don’t set any parameters this time.

Step 3. Press [Graph] to obtain the graph shown in Figure 2. Note that the graph is difficult to read near the origin, so we will adjust the viewing window next.

Figure 2

Step 4. Press [Zoom] and select Zoom In from the menu that appears. Simply scroll down to Zoom In and press [Enter]. Move the cursor to the origin on the graph. Press [Enter]. Now, the graph shown in Figure 3 appears, and the behavior of the graph near the origin is clear.
Figure 3

The viewing window is adjustable and the window parameters used in Figure 3 may be seen by pressing [Window]. These parameters are shown in Figure 4. The viewing window is defined by [pic] and [pic] The distances between tick marks are Xscl and Yscl for the x and y axes, resp.

The viewing parameters may be set manually by editing the existing values. For example, if the viewing window parameters are set as in Figure 5, then the graph of Figure 6 results when [Graph] is pressed.

Figure 5

Several special viewing windows are available on the Zoom menu. These include: Standard window which has [pic][pic] Decimal window in which the horizontal...