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प्रश्न
Write the total number of one-one functions from set A = {1, 2, 3, 4} to set B = {a, b, c}.
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उत्तर
A has 4 elements and B has 3 elements.
Also, one-one function is only possible from A to B if (A) ≤ n (B).
But, here n B if (A) > n (B).
So, the number of one-one functions from A to B is 0.
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