HP 49g Graphing Calculator - Manual (Page 106)

The tools discussed below are available from the
functions
sub-menu
(labeled
fcn
on the
PICT
menu).
1. Press
FCN
to display the
FUNCTIONS
menu.
2. Press the function key for the analysis tool you want.
Wlien you choose a fimction analysis tool, the menu is hidden to make
room for the result. You can restore the menu by pressing any one of the
fimction keys;
(FD
to {£6).
Finding roots
A root is a point where a graph meets or crosses the x axis. To find the
root closest to the cursor, press
ROOT
on the
FUNCTIONS
menu.
If the root is within the display area, the cursor moves to the root and the
value of the root is displayed near the bottom left comer of the screen. If
tlie root is not within the display area, the cursor remains where it is, the
message
OFF SCREEN
is briefly displayed, and the value of the root is
displayed near the bottom left comer of the screen.
If you want to find another root, move the cursor so that it is closer to that
root than to any other root before selecting
ROOT.
The message “Constant?” appears on the screen if the same value was
calculated at every sample point.
Function analysis tools list
Finding extrema
An extremum is the maximum or minimum value. To find the extrema
closest to the cursor, press
extr
on the
functions
menu.
If an extremum is within tire display area, the cursor moves to the point
and the x and y coordinates of the extremum are displayed near the
bottom left corner of the screen. If the extremum is not within the display
area, the cursor remains where it is, the message
OFF SCREEN
is briefly
displayed, and the x and y coordinates of the extreimun are displayed
near the bottom left comer of the screen.
If the derivative changes sign at the extremum, the message “Sign
Reversal” briefly appears on the screen before the coordinates are
displayed.
Page 4-38 Plotting graphs