Accents

We use several different kinds of accents in mathematics: a hat, bar, dot, and arrow over a variable all have different meanings. LaTeX uses commands that surround the variable:

$\hat{a}, \dot{a}, \ddot{a}, \tilde{a}, \bar{a}, \vec{a}$

yields

$\hat{a}, \dot{a}, \ddot{a}, \tilde{a}, \bar{a}, \vec{a}$

Practice: Try each of these commands out before continuing.