Set of real number is represented by the ℝ symbol. For this, you need to pass the argument R in \mathbb command in latex.

Symbol | Real numbers |

Type | Set |

Package | asmmath,… etc |

Command | \mathbb{R} |

Example | \mathbb{R} → ℝ |

In latex, this \mathbb command is located in more than one package. So, you look at this table below

amsfonts | \mathbb{R} → |

amssymb | \mathbb{R} → |

txfonts | \mathbb{R} → |

pxfonts | \mathbb{R} → |

Real number symbol structure is the same for amsfonts and amssymb packages but slightly different for txfonts and pxfonts packages.

```
\documentclass{article}
\usepackage{amsfonts}
\begin{document}
$$ a,b\in\mathbb{N} $$
\end{document}
```

**Output :**

## Real part from complex number in LaTeX

A complex number is made up of two parts, real and complex. And the real part is identified by the **ℜ(z)** symbol. By default, the \Re(z) command is used to define this **ℜ(z)** symbol

```
\documentclass{article}
\begin{document}
$$ z=a+ib $$
$$ \Re(z) = a $$
\end{document}
```

**Output :**

You can denote real part symbols using more different methods instead of the default method in latex. For example

**1.** Using a physics package that contains \Re command to denote the real part. And \Re command return **Re**(**z**) symbol instead of **ℜ**(**z**) symbol.

```
\documentclass{article}
\usepackage{physics}
\begin{document}
$$ z = a+ib $$
$$ \Re(z) = a $$
\end{document}
```

**Output :**

**2.** Secondly, you use the amsmath package. And re syntax must be passed into the \operatorname command.

```
\documentclass{article}
\usepackage{amsmath}
\begin{document}
$$ z = a+ib $$
$$ \operatorname{Re}(z) = a $$
\end{document}
```

**Output :**

**3.** Thirdly being amsfonts can be used to present the \mathfrak command. And you can pass both R and Re as arguments in this \mathfrak command.

```
\documentclass{article}
\usepackage{amsfonts}
\begin{document}
$$ z = a+ib $$
$$ \mathfrak{R}(z) = a $$
$$ \mathfrak{Re}(z) = a $$
\end{document}
```

**Output :**

If you look at the above outputs, you will understand that it is best to use **Re**(**z**) instead of **ℜ**(**z**) to denote the real part symbol. And for this, using the physics package and \Re command is the best practice.