Samsung Galaxy Book3 User Manual page 28

Basics
3
Connect the power cord to the external display.
4
Turn on the display and change its display mode to one
that supports an external input.
5
Press and hold the Fn key and press the F4 key.
6
Select a mode.
PC screen only
Show the screen on the computer monitor
only.
Duplicate
Show the screen on both the computer and the
external display.
Extend
Extend the screen to the external display.
Second screen only
Show the screen on the external display only.
You can also select the display mode in Windows
settings.
Select the Start button ( ) → Settings → System →
Display → Multiple displays and select Detect next to
Detect other display.
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