Consider performing a
HW 5 Greatest Hits
Note the difference between ordered pairs (or tuples) ((1,2,3,\dots)) and sets (\{1,2,3,\dots\}). Also note that a set cannot have duplicate elements (i.e. \{1,1\}=\{1\}).
- There's no "associative law" accross different operators, e.g. union and intersection.
|A-B|=|A|-|B| is not true. Can you find a counterexample?
Don't confuse \{\emptyset\} and \emptyset.
- Read problem instructions carefully, and make sure you do the right problems.