(The following is mainly excerpted from "A Not-Too-Brief Introduction to LATEX2e" )
1. Indexes and subscripts can be implemented by adding corresponding characters after ^ and _. for example:
2. The input command for square root is: \sqrt, and the n-th root is correspondingly: \sqrt[n]. The size of the square root symbol is automatically adjusted by LATEX. You can also use \surd to give only
symbols. for example:
3. The commands \overline and \underline draw horizontal lines above and below the expression. for example:
4. The commands \overbrace and \underbrace give a horizontal brace above and below the expression.
5. Vectors are usually represented by variables with arrow symbols above them. This can be obtained with \vec. Two other commands, \overrightarrow and \overleftarrow, are useful when defining a vector from A to B.
6. Fractions are typeset using \frac{...}{...}. In general, the 1/2 form is preferred because it looks better for a small number of fractions.
7. The integral operator is generated with \int. The sum operator is generated by \sum. The product operator is generated by \prod. Upper and lower bounds are generated with ^ and _, similar to superscripts and subscripts.
The following are the representations of some commonly used symbols
