HP 39g Graphing Calculator - Manual (Page 54)

To box zoom The Box Zoom option lets you draw a box around the area you
want to zoom in on by selecting the endpoints of one diagonal
of the zoom rectangle.
1. If necessary, press lgl=l>lM to turn on the menu-key labels.
2. Press and select l3Sm.
3. Position the cursor on one comer of the rectangle. Press
4. Use the cursor keys
(Q, etc.) to drag to the
opposite corner.
f -T-N. .r
' I
SELECT SECDND CC RNEIt HSKBlEiM
Press H3 to zoom in on
the boxed area.
To set zoom
factors 1. In the Plot view, press
2. Press PEI
3. Select Set Factors. . . and press EH.
4. Enter the zoom factors. There is one zoom factor for the
horizontal scale (XZOOM) and one for the vertical scale
(YZOOM).
Zooming out multiplies the scale by the factor, so that a
greater scale distance appears on the screen. Zooming in
divides the scale by the factor, so that a shorter scale
distance appears on the screen.
2-12 Aplets and their views