Question

write the complement of a and u if u is {c,a,t,,a,r,a,c,t}and a is {r,a,t} .findA'

Answer 1

Given A and B are two sets with number of elements p and q respectively.

The cartesian product of A and B=A×B={(a,b):(a∈A) and (b∈B)}

Number of elements in A×B=∣A×B∣=∣A∣.∣B∣=pq

Any relation from A to B is a subset of A×B.

Hence number of relations from A to B is the number of subsets of A×B

=2

∣A×B∣

=2

pq