Factorials

Definition

Factorials are mathematical operations that involve multiplying a number by all the positive integers less than it. For example, 5 factorial (written as 5!) is equal to 5 x 4 x 3 x 2 x 1.

Related terms

Permutations: Permutations refer to the different ways in which objects can be arranged or ordered. It is often used in combinatorics and involves factorials.

Combinations: Combinations also deal with arranging objects, but unlike permutations, they focus on selecting a subset of objects without considering their order.

Binomial Coefficients: Binomial coefficients are numbers that appear as coefficients in binomial expansions. They are calculated using combinations and involve factorials as well.