17 commands, each with the package it needs
Abstract
Hats, bars, arrows, dots and braces over or under a letter. Each takes an argument; the wide forms stretch over several letters. Table 1 lists every symbol of the category with its rendered glyph, the command to type and the package to load; each name links to a page with a worked example, and 3 of them to a note comparing the commands that compile.
| Glyph | Command | Package | Page |
|---|---|---|---|
\hat{x} | none | Hat | |
\tilde{x} | none | Tilde | |
\bar{x} | none | Bar | |
\overline{x} | none | Overline | |
\overbrace{x}^{n} | none | Overbrace | |
\underbrace{x}_{n} | none | Underbrace | |
\vec{x} | none | Vec | |
\dot{x} | none | Dot | |
\ddot{x} | none | Ddot | |
\acute{x} | none | Acute | |
\grave{x} | none | Grave | |
\check{x} | none | Check | |
\breve{x} | none | Breve | |
\mathring{x} | none | Mathring | |
\widehat{xy} | none | Widehat | |
\widetilde{xy} | none | Widetilde | |
\underline{x} | none | Underline |
Table 1. Math accents in LaTeX: glyph, command, package (none means built into LaTeX) and the page for each symbol. Commands go inside math mode unless the page says otherwise.
The same table exists for every family of symbols. To find one by name or by pasting the character, use the symbol search.