## Mathematical text in a line should be enclosed between dollar signs: $x<y$

## Even simple variable names should be in math mode: $x$

## Use _ and ^ for super- and subscripts: $x_i^2$

## There are commands for many math symbols: \epsilon, \rightarrow, \cup, \times, \subset, \sum

## Use double dollar signs for math on a line by itself: $$\sum_{n=0}^\infty \frac{x^n}{n!}$$