> For the complete documentation index, see [llms.txt](https://overleaf-pro.ayaka.space/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overleaf-pro.ayaka.space/latex/de/latex-fehler/02-command-r-invalid-in-math-mode-on-input-line-xxx.md).

# Befehl \r ist im Mathematikmodus in Zeile XXX ungültig

Dieser Fehler tritt auf, wenn Sonderzeichen im Mathemodus falsch verwendet werden. In LaTeX können bestimmte Zeichen wie Akzentbuchstaben oder Buchstaben mit Umlauten nicht im Mathemodus geschrieben werden. Der beste Weg, dies zu lösen, ist, sie innerhalb des **`\text{...}`** erkunden, die von dem **`amsmath`** Paket an.

## Häufige Ursachen

**Buchstaben mit Akzenten, Umlauten usw. im Mathemodus einfügen:**

z. B. ist ö eigentlich {\\"o}

**Spezielle Symbole im Mathemodus verwenden:**

z. B. ist Ångström \AA eigentlich \r{A}


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