June 16, 1997
1. Find all the subsets of the following sets:
(a) {1,2,3}
(b) { }.
2. Find the following Cartesian products:
(a) {
(b) {
3 (a) If a set A is not a subset of B and ,
then does
hold ? Give your reason.
(b) Prove .
4 (a) Recursively define the set of odd integers.
(b) Recursively define the set of natural numbers which produce 2 for the remainder
when divided by 3.
5. Prove the following by induction:
(a) .
(b) if
for i = 1,2, ..., n.
Logical Equivalences and Implications