Mở trình đơn Apple. Nhấn System Preferences… (Tùy chọn Hệ thống). Nhấp vào Displays (Màn hình). Nhấp vào thẻ Displays nằm ở góc trên bên trái của cửa sổ. Thay đổi độ phân giải của TV. Thay đổi tỉ lệ màn hình. Nhấp vào thẻ Arrangement (Sắp xếp) nằm ở đầu cửa sổ. Bỏ chọn hộp "Mirror displays" (Hiển thị song song). Di chuyển biểu tượng màn hình TV nếu cần. Dùng màn hình TV được mở rộng.

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Click the Apple logo in the top-left corner of the screen. A drop-down menu will appear. It's near the top of the drop-down menu. Doing so opens the System Preferences window. This computer monitor-shaped icon is in the middle of the System Preferences window. It's in the upper-left corner of the window. Check the "Scaled" box, then click a resolution. You can't use a resolution that's higher than your TV's built-in resolution (e.g., 4K). Click and drag the "Underscan" slider that's at the bottom of the page left to show more of your Mac's screen on the TV or right to zoom in the screen. This will help you fit your Mac's screen to your TV if the image on the TV is too large or too small. You'll find this option at the top of window. This will prevent the TV from merely duplicating what you see on your Mac. Skip this step if the box is unchecked. The TV's screen icon, which is usually the larger rectangle at the top of the window, should be to the right of your Mac's screen icon. You can click and drag the TV's icon to the right if necessary. The screen icon with the white bar at the top of it is your Mac's screen. Moving your mouse all the way to the right edge of your computer will move the mouse onto your TV's screen, where you can proceed to use the computer like usual. Any content on your computer's screen will remain as it was before extending the display.