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The value of  is equal to:

  2. n(n-1)!
  3. (n!)2

Answer (Detailed Solution Below)

Option 4 :
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Detailed Solution

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Concept:

  • The factorial (n!) is defined as the product of first n natural numbers.
  • n! = n × (n - 1) × (n - 2) × … × 2 × 1.

 

Calculation:

We know that (n + 1)! = (n + 1) × n × (n - 1) × (n - 2) × ... × 2 × 1 = (n + 1) × n!.

.

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