Use your TV as a display with Mac
You can use many kinds of TVs as computer displays. To connect your Mac to your TV, you need a video cable that connects your computer’s display port to the video input port on your TV. If you can’t find a cable that connects the ports on your Mac and TV, you may need an adapter for the cable. (You can also use AirPlay. See Stream video and audio with AirPlay.)
If you have an HDTV and a Mac with a Thunderbolt port 
, Mini DisplayPort 
or HDMI port, you may also be able to play audio from your computer on your TV.
Note: If your Mac has a Mini DisplayPort , make sure you use a cable (and adapter, if necessary) that supports both audio and video.
Connect your Mac to your TV
Connect one end of the video cable (or an adapter; if necessary) to the computer’s Thunderbolt port
, HDMI port or DVI port , then connect the other end of the cable to the TV’s video input port.If you need to adjust the resolution on your TV, choose Apple menu
in the sidebar. (You may need to scroll down.)Select a resolution or click Default to automatically use the best resolution.
If you want your HDTV to play audio as well as video from your Mac, choose Apple menu > System Settings, click Sound
in the sidebar (you may need to scroll down), then click Output.Select your HDTV in the list of devices. If you want to play audio on a different device (such as your computer’s speakers or an AV receiver that’s part of your sound system), select it instead.
Check whether you can play audio from your Mac on your TV
Your TV may be able to play audio from your Mac. If your Mac as a Thunderbolt or HDMI port, it can send audio to your HDTV. If your Mac has a Mini DisplayPort, it may be able to send audio to your HDTV.
Choose Apple menu
in the sidebar. (You may need to scroll down.)Click About, then click System Report.
In the sidebar, in the Hardware section, select Audio.
A list of your computer’s audio devices appears. If HDMI Output or HDMI/DisplayPort output is listed, your computer’s Mini DisplayPort can send audio.