Question

If set A has 2 elements and set B has 3 elements then how many subsets does A X B have?

(a) 6

(b) 8

(c) 32

(d) 64

The question was posed to me in an online quiz.

My question comes from Cartesian Product of Sets in division Relations and Functions of Mathematics – Class 11

Answer 1

Right choice is (d) 64

To explain: If set A has m elements and set B has n elements then A X B has m*n elements.

We know, a set has 2^r subsets if it has r number of elements.

Here, A X B has 2*3 = 6 elements. So, number of subsets of A X B will be 2^6 i.e. 64.