Ways to create 2 distinguishable committees
From a group of 11 people, how many ways are to create 2 distinguishable committees in which at least one person is in both committees?
I'm having a hard time understanding what to do with the second committee. I think for the first one, since it does not specify any number of people that have to be in either committee, there should be 2^11 ways to create it, minus 1 because there can't be an empty committee (because there must be at least one person in both). I'm not sure where to go from here to find how many ways there are to create the second committee.