Greater or Less
$a \gt b$
a \gt b
In MathJax, we use \gt because > has a special meaning on the web. It comes from "greater than".
$a \geq b$
a \geq b
\geq is a combination of "greater than" and "equal".
$a \geqq b$
a \geqq b
If you use \geqq, you will have one more horizontal line than with \geq.
$a \lt b$
a \lt b
In MathJax, we use \lt because < has a special meaning on the web. It comes from "less than".
$a \leq b$
a \leq b
\leq is a combination of "less than" and "equal".
$a \leqq b$
a \leqq b
If you use \leqq, you will have one more horizontal line than with \leq.
$a = b$
a = b
We use the symbols as it is.
$a \neq b$
a \neq b
\neq comes from "not equal". It can also be written as \ne or \not=.
$a \fallingdotseq b$
a \fallingdotseq b
\fallingdotseq is a combination of "falling dots" and "equal".
$a \sim b$
a \sim b
\sim comes from "similar".
$a \simeq b$
a \simeq b
It is a combination of "similar" and "equal". If you write \eqsim, the symbols above and below will be swapped
$a \approx b$
a \approx b
\approx comes from "approximately".
$a \gg b$
a \gg b
If you write "\gg", two > overlap.. If you write "\ggg", three > overlap.
$a \ll b$
a \ll b
If you write "\ll", two < overlap.. If you write "\lll", three < overlap.
$\max f(x)$
\max f(x)
$\min f(x)$
\min f(x)
$\begin{eqnarray} \max ( a, b ) = \begin{cases} a & ( a \geqq b ) \\ b & ( a \lt b ) \end{cases} \end{eqnarray}$
\begin{eqnarray}
\max ( a, b )
=
\begin{cases}
a & ( a \geqq b ) \\
b & ( a \lt b )
\end{cases}
\end{eqnarray}
The eqnarray environment is used to display multiple expressions. The cases environment is used to write cases.