1, the practical application of factorial reality: To know the probability of winning the first prize, it is1/c (32,7) = 7! *(32-7)! /32! =0.000000297;

2. The factorial of positive integers is the product of all positive integers less than or equal to this number, and the factorial of 0 is 1. The factorial writing of natural number n! . In 1808, Keston Kaman introduced this notation;

3. The factorial of positive integers is the product of all positive integers less than or equal to this number, and the factorial of 0 is 1.

Extended data:

Introduction to factorial:

For general plural,? The product of congruences of all modules n less than or equal to │n│ means that its real part and imaginary part must meet certain conditions.

n！ The factorial of a fraction in which n is a decimal or cannot be written as an integer is called generalized factorial. In addition, it should be noted that this factorial cannot be written as1× 2× …× n.

Factors are mainly used in the calculation of permutation and combination, and gamma function and gamma function are also related to factorial.

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