HP 39g+ User Manual page 53

To set zoom factors
Aplets and their views
5. Press to zoom in
on the boxed area.
1. In the Plot view, press
2. Press .
3. Select Set Factors... and press
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.
.
.
2-13