3-7-1

Using Trace

3-7 Using Trace

Trace lets you move a point along a graph and displays the coordinates for the current pointer location. You can also link the trace operation to the number table used to draw a graph, so the pointer jumps to the coordinates that are currently selected in the table.

Using Trace to Read Graph Coordinates

Starting the trace operation causes a crosshair pointer to appear on the graph. You can then press the cursor key or tap the graph controller arrows to move the pointer. The coordinates are displayed as you move the pointer.

STo perform a trace operation

Example: To graph the function y = x2 – 3 and then use the trace operation to read coordinates on the graph

(1)Tap to display the View Window dialog box, and then configure it with the following parameters.

xmin = –5, xmax = 5, xscale = 1

ymin = –10, ymax = 10, yscale = 2

(2)On the Graph Editor window, input and store x2 – 3 into line y1, and then tap to graph it.

(3)Tap [Analysis], [Trace], or tap .

The pointer will not be visible when it is located at a point outside the graph display area.

If “Error” appears in place of the xc or yc coordinate, it means that the current point is undefined. Press the left or right cursor key to move to a point that is defined.

(4)Press the left or right cursor key, or tap the left or right graph controller arrow.

This moves the pointer along the graph, and displays the coordinates of the current pointer location.

20060301