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Manipal MET2019MathematicsProbability

One mapping (function) is selected at random from all the mappings of the set A= 1,2,3, , n into itself. The probability that the mapping selected is one-one, is

Options

  1. An! n^ n-1
  2. Bn! n^n
  3. Cn! 2 n^n
  4. DNone of these

Correct answer

B. n! n^n

Step-by-step solution

Total number of mappings from a set A having elements into itself is n^n . And the total number of one to one mapping is n! Required probability = n! n^n .

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