Question:medium
Let \( f: A \to A \) be a function, where \( A = \{1, 2, 3, 4, 5, 6\} \). The number of one-one functions such that \( f(1) \le 3 \), \( f(3) \le 4 \) and \( f(2) + f(3) = 5 \), is:
Let \( f: A \to A \) be a function, where \( A = \{1, 2, 3, 4, 5, 6\} \). The number of one-one functions such that \( f(1) \le 3 \), \( f(3) \le 4 \) and \( f(2) + f(3) = 5 \), is:
Show Hint
In counting problems with multiple constraints, always start with the most restrictive condition (here, the sum \( f(2)+f(3)=5 \)) to limit the search space immediately.
Updated On: Apr 6, 2026
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The Correct Option is B
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