# 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.