latex

# How to Write and Use Infinity Symbol in LaTeX

The infinity or lemniscate symbol represents infinity or a never-ending expression. The infinity symbol is denoted as ‘∞,’ which you can use in mathematics or physics. The symbol plays an important role in technical documents and research papers.

That’s why document processors support source codes to write an infinity symbol. However, it sometimes becomes challenging to create an infinity symbol in document processors like LaTeX. So if you also want to learn it, here’s a tutorial on how to use and write infinity symbols in LaTeX (document processor).

## How to Write and Use an Infinity Symbol in LaTeX?

You don’t need a \usepackage to write the infinity symbol, so please use the following source code to write it:

\begin{document}

$$\infty$$

\end{document}

Output

Similarly, you can use the negative infinity symbol through the following source code in LaTeX:

\begin{document}

$$-\infty$$

\end{document}

Output

You can use the following source codes to write different types of infinity symbols in LaTeX:

 Codes Output 0\cdot\infty \left ( +\infty ,-\infty \right ) 1^{\infty} \infty-\infty \frac{\infty}{\infty} \infty^{0}

### Examples of Infinity Symbols in Mathematics

The infinity symbol is required to represent the limit, and you can write it through the following source code:

\documentclass{article}

\begin{document}

If $f(x)= 4x^2-18x^3+9$, then find the following:

$$\lim_{x \to -\infty}f(x)$$

$$\lim_{x \to \infty}f(x)$$

\end{document}

Output

You can use the infinity symbol in integral equations:

\documentclass{article}

\begin{document}

$$\int_{b}^{\infty}e^{kx}\:dx$$

$$\int_{b}^{\infty}x^{p}\:dx$$

$$\int_{b}^{\infty} \frac{(\ln x)^{q}}{x}\:dx$$

\end{document}

Output

## Conclusion

This was all about the source codes to write and use infinity symbols in LaTeX. Both ∞ and -∞ are simple to write because they only require simple source codes. If you want to know more about the cool stuff of LaTeX, please visit our official website.