Asus G73JHBST7 Manual page 58

Scrolling - Use one fingertip to slide up/down/left/right on the
touchpad to scroll a window up/down/left/right. If your display
window includes several sub-windows, move the pointer on that
pane before scrolling.
Scrolling vertically
Two-finger zooming in/out - Moving two fingertips apart or
together on the touchpad to zoom in or zoom out. This is convenient
when viewing photos or reading documents.
Zooming in
58
Scrolling
horizontally
Zoooming out
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