 represents the set that contains all the elements that are in at least one of the sets, so
 represents the set that contains all the elements that are in at least one of the sets, so 
 .
.
We want the complement of this set (in other words, the set with all the elements in the universal set but not in the given set).
This set is {3, 4, 11, 13, 14, 15, 17, 24}