Some of the most common commands include:

**Fractions and Square Roots:**For fractions, use`\frac {numerator}{denominator}`

. For square roots, use`\sqrt[root]{number}`

.**Greek letters:**use the commands given in the table below:

**Operators:**`\leq`

gives the less than or equal to symbol,`\geq`

gives the greater than or equal to symbol,`\neq`

gives the not equal symbol,`\sum`

gives the summation symbol,`\partial`

gives the partial derivative symbol,`\nabla`

gives the Laplacian operator,`\times`

gives the cross product or multiplication symbol,`\cdot`

gives the dot product or multiplication symbol, and`\int`

gives the integral symbol.**Arrows:**`\rightarrow`

and`\leftarrow`

give right and left arrows, respectively.**Percents:**If typing % in LaTeX, it is important to include a backslash,`\%`

as the percent symbol is normally used for comments.**Superscripts and Subscripts:**To do a superscript, you can type`x^2`

, or, for longer superscripts,`x^{2x}`

. To do a subscript, you can type`x_a`

, or, for longer subscripts,`x_{ab}`

.**Bold:**Use`\boldmath{...}`

to make your math symbols bold. Other options are given at this TeX.SX question. Math symbols are automatically italicized; if you don't want this to be true, make your equation text as described below.**Infinity:**To write infinity, use the command`\infty`

.**Moving items over or under another:**First, for math operators only, there is an alternate method. You can type the math operator, say`\int`

, and then use the`\limits`

command. An example is`\int\limits_{\infty}`

or`\int\limits^{\infty}`

. Then, for normal cases, you can do`\overset{top}{normal}`

or`\underset{bottom}{normal}`

. This can be very useful for doing vectors. For example, you might do`\overset{\rightarrow}{x}`

The`amsmath`

package is need for`overset`

and`underset`

.**Curly Braces:**Because curly braces are used in commands, it is necessary to type`\{`

or`\}`

to get curly braces.**Text:**To include text in equations, type`\usepackage{amsmath}`

in the preamble, and then type`\text{...}`

.**Space:**To add space in your equations, type`\quad`

between the two items you want to separate (for example, you might have`$2x \quad cos`

).