Factorial of a number: We define factorial (n) such that

We define factorial (n) such that if n = 0 or n = 1, it returns 1 (base case); otherwise, it returns n × factorial (n - 1). Thus, the problem is broken down into smaller subproblems until reaching the base case. In Mathematics, factorial is an important function, which is used to find how many ways things can be arranged or the ordered set of numbers. The well known interpolating function of the factorial function was discovered by Daniel Bernoulli. The factorial concept is used in many mathematical concepts such as probability, permutations and combinations, sequences and series, etc. In short, a factorial is a function that multiplies a number by every number below it till 1. For example, the ... The factorial of a positive number n is given by: factorial of n (n!) = 1 " 2 " 3 " 4....n The factorial of a negative number doesn't exist. And, the factorial of 0 is 1. The factorial of a number is the product of all positive integers from that number down to 1. It plays a key role in many mathematical concepts, such as permutations, combinations, probability, and more.