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Fact

FACT Function

The FACT function in Excel calculates the factorial of a number. A factorial of a number is the product of all integers from 1 to that number. It's denoted as n!, where n is the number, and is essential in various mathematical and statistical calculations.

Syntax:

FACT(number)
  • number: The non-negative number for which you want to calculate the factorial. If the number is not an integer, it is truncated.

Examples:

  1. =FACT(5) would return 120, since 5! (factorial of 5) is 1 * 2 * 3 * 4 * 5 = 120.
  2. =FACT(3) would return 6, as 3! is 1 * 2 * 3 = 6.
  3. =FACT(0) returns 1, because the factorial of 0 is defined as 1.

Usage Notes:

  • Factorials are commonly used in permutations and combinations, probability theory, and in various functions of algebra and calculus.
  • The FACT function only works with non-negative numbers. If a negative number is provided, it will result in an error.
  • For large numbers, the result of FACT can be very large and might exceed Excel's capacity for number storage, leading to an error or an overflow.

Note: Factorials grow extremely rapidly with larger numbers, so it's common to encounter large outputs even for relatively small inputs in the FACT function.