---
title: "Equations"
description: "Write mathematics and chemistry on cards with KaTeX."
---

> Documentation Index
> Fetch the complete documentation index at: https://docs.armincards.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Equations

Cards render mathematics with KaTeX. Use **Edit source** in the card editor to
write equations.

| You write                              | You get                            |
| -------------------------------------- | ---------------------------------- |
| `$x^2$` or `\(x^2\)`                   | Inline math                        |
| `$$\frac{a}{b}$$` or `\[\frac{a}{b}\]` | A display equation on its own line |
| `$\ce{H2O}$`                           | Chemistry, inside math delimiters  |

Code spans and code blocks stay literal, so you can show LaTeX source without
rendering it. If a command isn't supported, Armin keeps its source and shows a
warning in the preview.

Source: https://docs.armincards.app/guides/equations/index.mdx