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Let A = a , b , c and B = 1 , 2 , 3 , 4 . Then the number of elements in the set C = f : A → B ∣ 2 ∈ f ( A ) and f is not one-one is …

Correct answer

19

Step-by-step solution

only ' 2 ' in range → 1 function. Total no of many one function without any condition = 60-24=40. Number of many one function with 2 is not in range =27-6 =21. Therefore no of not one-one functions with 2 in range = 40-21=19.

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