You mean headphone OUTPUT on the TV, but thats just nit picking

You can do it that way, which would work (and should also bypass the TV speakers meaning that the sound is only coming from the 2.1 system)

Or if you want the TV speakers to work and have the option of having the 2.1 playing TV sound without having to unplug the cable from the headphone output on TV, you get a Scart to composite adapter;



And one of these leads : twin RCA to stereo mini-jack;



Plug the red an white RCA's into the red and white phono sockets on the scart adapter, set the adapter to OUT and plug it into the TV scart socket. Plug the other end (minijack) of the cable to your 2.1 system.

Then you will have sound from the 2.1 speakers AND the TV speakers - set the speakers up behind you and you have a poor mans "surround sound" set up stereo fronts and stereo rears, and a sub - bit like 4.1