> 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/da/latex-fejl/13-latex-error-can-be-used-only-in-preamble.md).

# LaTeX-fejl: Kan kun bruges i præamblen

Denne fejl vises, når du har inkluderet en pakke eller klasse i hoveddelen af dit dokument i stedet for i præamblen. Dokumentets præambel består af alt, der er skrevet før **`\begin{document}`**. I præamblen definerer du den type dokument, du skriver, sproget og flere andre elementer. For eksempel vil en normal dokumentpræambel se sådan ud:

```latex
\documentclass[12pt, letterpaper]{article}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}

\title{Første dokument}
\author{Hubert Farnsworth \thanks{finansieret af ShareLaTeX-teamet}}
\date{Februar 2014}
```

Hvis du skriver **`\usepackage{...}`** i dokumentets hoveddel (efter **`\begin{document}`**) i stedet for i præamblen, vil du generere fejlmeddelelsen vist nedenfor.

main.tex, linje 7

LaTeX-fejl: Kan kun bruges i præamblen.

Se LaTeX-manualen eller LaTeX Companion for en forklaring. Skriv H for øjeblikkelig hjælp. ... l.4 \usepackage {amsmath} Din kommando blev ignoreret. Skriv I for at erstatte den med en anden kommando, eller fortsætte uden den. \[1

For at rette denne fejl skal du sørge for, at alle **`\usepackage{...}`** kommandoer, såvel som **`\documentclass[...]{...}`**, er skrevet før **`\begin{document}`**. For at lære mere om, hvordan man strukturerer et dokument i LaTeX, så tjek vores [dokumentationen](/latex/da/latex-grundlaeggende/01-learn-latex-in-30-minutes.md).


---

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