Expanding Polynomials: Factorial Notation - Expii

Learn about the factorials 0! = 1, 1! = 1, 2! = 2, 3! = 6, ... defined by the recursive formula n! = n×(n-1)! for n>0. Here n! is the product of the numbers from 1 to n, which gives a convenient way to compute the "binomial coefficients" appearing in the binomial theorem.