Symbol | Factorial |
---|---|

Type of symbol | Mathematics |

Package (requirement) | No |

Argument | No |

Latex command | `!` |

Example | `a!` → a! |

A popular symbol used in mathematics is factorial, no command is required to print this symbol in a latex document. Just use bang or exclamation point key `shift`

+

on your keyboard.^{!} 1

```
\documentclass{article}
\begin{document}
$$ n! = n(n-1)(n-2)\cdots (2)(1) $$
$$ \frac{(n+1)!}{n!} $$
$$ \frac{(2n+2)!+(n!)^2}{((n+1)!)^2 (2n)!} $$
\end{document}
```

**Output :**

When using multiple factorials side by side, the space between them is not correct. In that case, you can use the following commands in LaTeX to provide spaces: `\,`

, `\enspace`

, `\quad`

. The example below shows how much space these commands provide.

```
\documentclass{article}
\begin{document}
$ \frac{1}{m!n!} \rightarrow \verb|{m!n!}| $\\[6pt]
$ \frac{1}{m!\,n!} \rightarrow \verb|{m!\,n!}| $\\[6pt]
$ \frac{1}{m!\enspace n!} \rightarrow \verb|{m!\enspace n!}| $\\[6pt]
$ \frac{1}{m!\quad n!} \rightarrow \verb|{m!\quad n!}| $\\[6pt]
\end{document}
```

**Output :**

In terms of spacing, you can see that `\enspace`

and `\quad`

use the command to take more space than `\,`

, which doesn’t look very good. But it looks much better to see that the space has been properly maintained using the `\,`

command. so I would recommend using `\,`

it in this case.

## Inverse factorial symbol in LaTeX

Generally, the inverse factorial symbol is not used that much, but if you need this symbol at some point, then using the backtick ```

symbol next to the factorial `!`

symbol will print the inverse factorial symbol in the latex document, use it like this `!``

. And you have to use it in text mode.

```
\documentclass{article}
\begin{document}
! $ \rightarrow $ \verb|Factorial symbol|\\[6pt]
!` $ \rightarrow $ \verb|Inverse factorial symbol|
\end{document}
```

**Output :**