Connect Audio Out of your cable box to Bose' Input. Connect Video Out (probably, HDMI) to your TV. Turn TV volume down to zero and leave it as that.
If your cable box does not have separate Audio Out, you would need "HDMI Audio Extractor" - a box with two HDMI connectors, and an optical out port. Plug it between cable box and TV, and plug TosLink optical cable to the Bose.
I am so glad your helping me..I'm doing connections with some bose speakers from 2009 and the t.v. is samsung 2017 hdtv 4 k. So the bose speakers only have the red and white cables no tosllink. And Thanks for your replies