User Guide

Chapter 17: Activities 308
Graphing Piecewise Functions
Problem
The fine for speeding on a road with a speed limit of 45 kilometers per hour (kph) is 50; plus 5 for
each kph from 46 to 55 kph; plus 10 for each kph from 56 to 65 kph; plus 20 for each kph from 66
kph and above. Graph the piecewise function that describes the cost of the ticket.
The fine (Y) as a function of kilometers per hour (X) is:
,
which simplifies to:
Procedure
1. Press z. Select Func and Classic.
2. Press o. Turn off all functions and stat plots. Enter the Y= function to describe the fine. Use
the
TEST menu operations to define the piecewise function. Set the graph style for Y1 to
í (dot).
3. Press p and set Xmin=L2, Xscl=10, Ymin=L5, Yscl=10 and @X=1. Ignore Xmax and Ymax;
they are set in step 4.