Q12 of 76 Page 2

Let A= {x, y, z} and B= {a, b}. Find the total number of relations from A into B.

The total number of relations that can be defined from a set A to a set B is the number of possible subsets of A × B. If n(A)=p and n(B)=q, then n(A × B)= pq. So, the total number of relations is 2pq.


n(A) = 3 and n(B) = 2 ⇒ n(A × B) = 3 × 2 = 6


∴ Total number of relations = 26 = 64


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