Question

if two sets A and B consists of elements bracket under 1345 bracket and Bracket 6 7 8 9 bracket respectively then find the number of element in bracket a union b bracket

Answer 1

A union B={1,3,4,5,6,7,8,9}
hope this will help

Answer 2

$\huge\underline\mathcal\purple{BTS \: EXO}$

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