You use dot symbols in different ways. Sometimes only dot symbols are used, sometimes more than one dot is used and dot symbols are used above and inside the letter.

In this tutorial, we will discuss in-depth the use of all kinds of dot symbols and latex commands.

## Simple dot symbol

In latex, the simple dot symbol is represented by the `\cdot`

command. And you may have seen its use in vector dot products.

Properties | Value |
---|---|

Symbol | Dots |

Package | default |

Argument | No |

Command | `\cdot` |

Example | `\cdot` →• |

```
\documentclass{article}
\begin{document}
\[ \cdot \]
\[ \vec{\imath} \cdot \vec{\jmath} \]
\end{document}
```

**Output :**

Also, you can take the help of **physics** package. Where the `\vdot`

command is used to define the vector dot product.

```
\documentclass{article}
\usepackage{physics}
\begin{document}
\[ \vdot \]
\[ \vec{p} \vdot \vec{q} \]
\end{document}
```

**Output :**

## Latex three dots symbol

When you use n number elements to represent a mathematical expression. In that case, the three-dot symbol is used without marking each element in the expression.

Dots Symbol | Command |
---|---|

Horizontal dots | `\ldots` |

Horizontal central dots | `\cdots` |

Vertical dots | `\vdots` |

Diagonal dots | `\ddots` |

Inverse Diagonal dots | `\iddots` |

Also, there are many commands. In this tutorial, we will only discuss the above five commands.

### 1. Horizontal dots on the line

You look at the program below. Three dots have been used along with the `\ldots`

command.

```
\documentclass{article}
\begin{document}
\[ a_{1}, a_{2},...,a_{n} \]
\[ a_{1}, a_{2},\ldots,a_{n} \]
\end{document}
```

**Output :**

In both cases, there is a difference between the output. In my opinion, it is better to use `\ldots`

command instead of using three dots.

### 2. Horizontal dots above the line

For example, the `\cdots`

command is used when the sum of n numbers is displayed.

```
\documentclass{article}
\begin{document}
\[ f(x)=x+ x^{2}+\cdots+x^{n} \]
\end{document}
```

**Output :**

I hope you understand the difference between `\ldots`

and `\cdots`

commands.

### 3. Vertical dots

Vertical dot consists of three-dot symbols, which are located vertically. And this symbol is represented by `\vdots`

Command.

```
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\[ \begin{bmatrix}
a_{1}\\
a_{2}\\
\vdots\\
a_{n}
\end{bmatrix} \]
\end{document}
```

**Output :**

You must install the **amsmath** package when denoting the matrix. And use the `\usepackage`

command when installing a package.

### 4. Diagonal dots symbol

This symbol is located along the diagonal from **N-W** to **S-E**. And this symbol is mostly used to represent the elements located along the diagonal of the matrix.

```
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{bmatrix}
a_{1} & & \\
& \ddots & \\
& & a_{n}
\end{bmatrix}
\end{document}
```

**Output :**

If you look at the program above, you will understand that `\ddots`

has been used for the diagonal dots symbol.

### 5. Inverse Diagnal dots symbol

The inverse diagonal dots symbol will be located along the **S-W** to **N-E** direction. There is more than one command to represent this symbol but this tutorial will only discuss `\iddots`

commands.

```
\documentclass{article}
\usepackage{amsmath}
\usepackage{mathdots}
\begin{document}
\[ \begin{bmatrix}
& & a_{1}\\
& \ddots & \\
a_{n} & &
\end{bmatrix} \]
\end{document}
```

**Output :**

To use the `\iddots`

command in Latex you need to install the **mathdots** package. Because there is no default command in latex to represent the inverse diagonal dots symbol.

## Latex dot derivative

When a variable is derivative in respect of time, the time derivative is represented by a dot symbol on the head of that variable.

```
\documentclass{article}
\begin{document}
\[ \frac{\mathit{d}r}{\mathit{d} t}=\dot{r} \]
\[ \frac{\mathit{d}^{2}r}{\mathit{d} t^{2}}=\ddot{r} \]
\end{document}
```

**Output :**