# Factorial Tutorial

## Factorial Tutorial

##### Definition:

The number of sequences that can exist with a set of items, derived by multiplying the number of items by the next lowest number until 1 is reached. In mathematics, product of all whole numbers up to the number considered. The special case zero factorial is defined to have value 0!=1, consistent with the combinatorial interpretation of there being exactly one way to arrange zero objects. The notation n factorial (n!) was introduced by Christian Kramp in 1808.

##### Example 1:

Calculate the Factorial of 4 ie., 4!.

###### Step 1:

Multiply all the whole numbers up to the number considered.
4! = 4*3*2*1 = 24

##### Example 2:

Simplify the following: 3! + 2!, 3! - 2!, 3! * 2!, 3! / 2!

###### Step 1:

Find the factorial of 3.
3! = 3*2*1 = 6

###### Step 2:

Find the factorial of 2.
2! = 2*1 = 2

###### Step 3:

Add 3! + 2!
3! + 2! = 6 + 2 = 8

###### Step 4:

Subtract 3! - 2!
3! - 2! = 6 - 2 = 4

###### Step 5:

Multiply 3! * 2!
3!*2! = 6*2 = 12

###### Step 6:

Divide 3! / 2!
3! / 2! = 6 / 2 = 3
This example will help you to find the factorial manually.

This tutorial will help you to calculate the Factorial problems like Factorial Addition, Subtraction, Multiplication, Division. Factorials are used in determining the numbers of combinations and permutations and in finding probability.