Find the power set of a, where a = { 2x is an element of z | 7 < x < 10, x is an element of z } .
2. let, a = {3n is an element of z | -1? n ? 3, n is an element of z } , b = {1, 2} and c = {{1,2}}. find a x ( b x c) .
3. use an element argument to prove the statement:
for all sets a and b, ac n bc is a subset of (a u b)c
4. for all sets a and b, simplify the given expression,
(a - (a n b)) n (b - (a n b))
cite a property from theorem 6.2.2 for every step of the proof.