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Question
If A = {a, b, c} and B = {−2, −1, 0, 1, 2}, write the total number of one-one functions from A to B.
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Solution
Let F : A → B be a one-one function .
Then , f (a) can take 5 values, f (b) can take 4 values and f (c) can take 3 values .
Then, the number of one-one functions = 5 × 4 × 3 = 60
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