\hat{a}, \tilde{a}
a_{i}, a^{j}
\gamma, \Gamma
\neq
\pm
\leq
\equiv
\approx
a \ldots b
a \cdots b
\ddots
\Rightarrow
\Leftrightarrow
\exists \forall
\in, \subset
\sum_{n=1}^{10} n+1
\int_{0}^{1} e^{x}
\, dx\iint xy
\, dx \, dy\sqrt{ \frac{x}{y} }
\left( \begin{array}{cc} a & b \\
c & d \end{array} \right)