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Question
Let A = {x, y, z} and B = {1, 2}. Find the number of relations from A to B.
Solution
Given A= {x, y, z) and B = {1, 2)
n(A) = 3 and n(B) = 2
Since n(A × B) = n(A) × n(B)
n(A x B) = 3 x 2 = 6.
The Number of relations from A to B is equal to the number of subsets of A x B.
Since A × B contains 6 elements.
=> Number of subsets of A × B = 26 = 64.
So, there are 64 relations from A to B.
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