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Question
If R is a relation from a finite set A having m elements of a finite set B having n elements, then the number of relations from A to B is
Options
(a) 2mn
(b) 2mn − 1
(c) 2mn
(d) mn
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Solution
(a) 2mn
Given: n(A) = m
n(B) = n
∴ \[n\left( A \times B \right) = mn\]
Then, the number of relations from A to B is 2mn.
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