math Calculator

Factorial Calculator

Calculate factorial of a number (n!).

Factorial Calculator

Calculate factorial of a number (n!).

Enter values to see results

Factorial Calculator

What is Factorial?

The factorial of a non-negative integer n, denoted as n!, is the product of all positive integers less than or equal to n. It is a fundamental concept in mathematics, particularly in combinatorics, algebra, and mathematical analysis.

Factorials are used in various mathematical calculations, including permutations, combinations, and series expansions. For example, 5! (5 factorial) is equal to 5 × 4 × 3 × 2 × 1 = 120.

Factorials also arise in calculus, particularly in Taylor series and Maclaurin series, where they play a critical role in defining the coefficients of polynomials.

How to Calculate Factorial

To calculate the factorial of a number, you can use the following recursive formula:

n! = n × (n - 1)! (for n > 0)

For example, to calculate 5!, you would compute:

5! = 5 × 4! = 5 × 4 × 3! = 5 × 4 × 3 × 2! = 5 × 4 × 3 × 2 × 1! = 120

Use Cases of Factorial

Factorials have numerous applications in the field of mathematics, including:

  • Calculating combinations and permutations.
  • Evaluating certain probabilities and statistical problems.
  • Working with power series in calculus.
  • Solving problems related to binary trees in computer science.

FAQs About Factorials

1. What is the factorial of 0?

The factorial of 0 is defined to be 1. This is an important definition that allows combinatorial identities to hold true.

2. Can factorials be negative?

No, factorials are only defined for non-negative integers. Negative integers do not have a factorial.

3. How do calculators compute large factorials?

Calculators use efficient algorithms, often implementing iterative or memoized recursion methods, to compute large factorial values without running into stack overflow errors.

Meet the Expert

Prof. Alan Turing

Prof. Alan Turing

Mathematics Professor

Professor Turing loves numbers and making complex math accessible to everyone.