PiecewiseDefined Functions on the TI83 Plus
When graphing a piecewisedefined function on the TI83 Plus graphing calculator, some people cop out and simply graph each of the separate functions that appear in it. But this does not result in an accurate graph. To accurately graph the following piecewisedefined function, perform the following steps:

Enter the functions Y_{1}, Y_{2}, and Y_{3} in the Y= editor.

Turn off Y_{1}, Y_{2}, and Y_{3} by unhighlighting their equal signs.
This is done in the Y= editor by using the
keys to place the cursor on the equal sign in the definition of the function and then pressing [ENTER] to toggle the equal sign between highlighted and unhighlighted. The calculator graphs a function only when its equal sign is highlighted.

Enter the piecewisedefined function in Y_{4} as
The function must be entered as it appears here, complete with parentheses.

To enter Y_{1}, Y_{2}, and Y_{3}: Press
and then press the number of the function you want to use in the definition.

To enter the inequalities: Press [2nd][MATH] to access the Test menu, and then press the number of the inequality you want to use in the definition. For example, to enter the lessthan (<) symbol, press [2nd][MATH][5].


Press [ENTER].

Graph the piecewisedefined function.