How to Graph Trig Functions on the TI-83 Plus

The TI-83 Plus graphing calculator has built-in features especially designed for graphing trigonometric functions. They produce graphs that look like graphs you see in text books; and when you trace these graphs, the x-coordinate of the tracing point is always given as a fractional multiple of

To use these features when graphing trigonometric functions, follow these steps:

1. Put the calculator in Function and Radian mode.

   Press [MODE]. In the third line, highlight Radian, and in the fourth highlight Func. (To highlight an item in the Mode menu, use the

   

   keys to place the cursor on the item, and then press [ENTER].)

2. Enter your trigonometric functions into the Y= editor.

3. Press [ZOOM][7] to graph the function.

   [ZOOM][7] invokes the ZTrig command which graphs the function in a viewing window in which

   

   and

   

   It also sets the tick marks on the x-axis to multiples of

   

   When you trace a function graphed in a ZTrig window, the x-coordinate of the trace cursor will be a multiple of