Trace Option
While viewing a graph, press 
and a blinking
cursor is displayed on the first graph entered. The cursor is positioned
at xmin defined in the window.
If the coordinates option is on, the coordinates of the
blinking cursor's location appear at the bottom of the screen.
If the derivative option is on, the
derivative at that point is displayed as well. Other information,
such as t for parametric or angle for polar graphs may be shown
depending on the type of graph.
Press 
or
to move the cursor
along the graph from one plotted point to the next.
Note: Press 
or
moves the tracing cursor to the next function,
as indicated by the number in the upper right corner of the screen.
The cursor moves to the new function at the same x value if it is defined at that value.
If tracing a graph takes the cursor off the display screen
to the left or right, the viewing window pans to show the new cursor
location. The window settings are updated accordingly.
If tracing a graph takes the cursor off the display screen to
the top or bottom, the cursor disappears from the screen. However, the
x and y coordinates of the cursor are displayed at the bottom
of the screen.