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Question
If A = {1, 2, 3} and B = {a, b}, write the total number of functions from A to B.
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Solution
Formula:
If set A has m elements and set B has n elements, then the number of functions from A to B is
Given:
A = {1, 2, 3} and B = {a, b}
⇒ n (A) = 3 and n (B) = 2
∴ Number of functions from A to B = 23 = 8
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