This is a primer and reference sheet for LaTeX focused on the symbols and commands used in online forums, like those of Coursera or Udacity, and when writing technical posts in content management systems, like WordPress, Joomla or Drupal.
LaTeX for web pages and forums
LaTeX is a set of commands to write beautiful pages developed by Leslie Lamport on top TeX developed by Donald Knuth. It is the default submission format for many conferences and journal papers. LaTeX is a complete layout and typographical system: it can format pages, manage graphs and pictures, write bibliographies.
However, there is already plenty of control of style in web pages via HTML, CSS and pre-formatted templates so LaTeX has a discrete role in their overall appearance; presently, its main role is to provide the commands to write beautiful math symbols, which are in much demand in technical forums and posts.
In-line vs. Own-line
The LaTex commands are written within the text, surrounded by a set of characters. These characters vary from place to place but usually are something like $, $%, $$ or similar.
There are two ways to add LaTeX to our writing:
1. inline, as part of the text as in:
..and that is why \(E = m\cdot c^2\) defines..
which we write as
..and that is why \(E = m\cdot c^2\) defines..
2. In its own line, as in:
$$ E=m\cdot c^2 $$
which we write as
$$ E=m\cdot c^2 $$
In this writing we will use \( and \) for inline commands and $$ for own-line ones. To post in:
- Udacity: use $% for inlines and $$ for own-lines.
- Coursera: use $$ for inlines and $$ for own-lines
Printing $ in inline text
A character much used for inline latex is a single $. This works well unless there happens to be a dollar sign in the text that LaTeX will then mistake for the beginning of an inline expression, e.g.,
..\(30 dollars or even \)40..
when really we were writing normal text:
..$30 dollars or even $40..
If we are having this problem is because the site that we are using set the default inline characters to $, a not recommended but unfortunately common practice.
If the site or forum is out of our control, the best we can do is to figure out how to print the $ the best we can. The following are partial solutions:
- write the text of the dollar sign in a pre-formatted text, as shown in the example above. The problem is that pre-formatted text appears in a box.
- write the dollar sign in Latex, which results in \(\$\).
- write the dollar sign in emphasized text, i.e., <em>$</em> which results in $
If the site is our own, we can do better by not setting a single $ as the default. Two possibilities that work well are:
- use the default used by Udacity, i.e., $%
- use another unusual combination, e.g., \$
or we can simply remove the option of using $ as a latex delimiter, i.e., switch the MathJax settings from:
MathJax.Hub.Config({tex2jax: {inlineMath: [[‘$’,’$’], [‘\\(‘,’\\)’]], processEscapes: true}});
to
MathJax.Hub.Config({tex2jax: {inlineMath: [[‘\\(‘,’\\)’]], processEscapes: true}});
Color and highlighting
..the \( \color{red}{Republican}\) and the \( \color{blue}{Democrat} \) parties who..
..the \( \color{red}{Republican} \) and the \( \color{blue}{Democrat} \) parties who..
..and Einstein, who in \( \bbox[yellow]{\mbox{1905}} \) published four papers..
..and Einstein, who in \( \bbox[yellow]{\mbox{1905}} \) published four papers..
The \mbox command
It is used to add normal text to Latex expressions:
\( \mbox{Energy} = m\cdot c^2\)
\(\mbox{Energy} = m\cdot c^2\)
Predefined function names
These are functions that LaTeX writes in normal text, without needing the \mbox command.
$$
\begin{array}{lllllllllllllll}
\mbox{\arccos} &\hspace{.01in} &
\mbox{\cos} &\hspace{.01in} &
\mbox{\csc} &\hspace{.01in} &
\mbox{\exp} &\hspace{.01in} &
\mbox{\ker} &\hspace{.01in} &
\mbox{\limsup} &\hspace{.01in} &
\mbox{\min} &\hspace{.01in} &
\mbox{\sinh}\\
\mbox{\arcsin} &\hspace{.01in} &
\mbox{\cosh} &\hspace{.01in} &
\mbox{\deg} &\hspace{.01in} &
\mbox{\gdc} &\hspace{.01in} &
\mbox{\lg} &\hspace{.01in} &
\mbox{\ln} &\hspace{.01in} &
\mbox{\Pr} &\hspace{.01in} &
\mbox{\sup}\\
\mbox{\arctan} &\hspace{.01in} &
\mbox{\cot} &\hspace{.01in} &
\mbox{\det} &\hspace{.01in} &
\mbox{\hom} &\hspace{.01in} &
\mbox{\lim} &\hspace{.01in} &
\mbox{\log} &\hspace{.01in} &
\mbox{\sec} &\hspace{.01in} &
\mbox{\tan}\\
\mbox{\arg} &\hspace{.01in} &
\mbox{\coth} &\hspace{.01in} &
\mbox{\dim} &\hspace{.01in} &
\mbox{\inf} &\hspace{.01in} &
\mbox{\liminf} &\hspace{.01in} &
\mbox{\max} &\hspace{.01in} &
\mbox{\sin} &\hspace{.01in} &
\mbox{\tanh}
\end{array}
$$
Tables
We can write a table using the array command followed by the format that each column, e.g., \begin{array}{l,c,r} will start a table with three columns, in which the first, second and third values will be printed to the left, center, and to the right of their respective columns. Columns are separated by &; lines are separated by \\.
$$
\begin{array}{lcr}
\mbox{Johnathan Doe} & \mbox{Washington} & $1023.95\\
\mbox{Jane Doe} & \mbox{Denver} & $248.96 \\
\mbox{Kitty Doe} & \mbox{Lake Tahoe} & $8.96
\end{array}
$$$
$$
\begin{array}{lcr}
\mbox{Johnathan Doe} & \mbox{Washington} & $1023.95\\
\mbox{Jane Doe} & \mbox{Denver} & $248.96 \\
\mbox{Kitty Doe} & \mbox{Lake Tahoe} & $8.96
\end{array}
$$
Usually lines are separated by \\ but in some forums, lines are separated by \\\ or even \\\\.
Spacing and dots
Spacing: We can insert small negative spaces with the \! command and thin, medium or thick spaces with \, \: and \;, respectively. Spaces of any size are inserted with the \hspace{} command:
$$ T\!\!\!\!\!X\hspace{0.5in}|\,|\hspace{0.5in}|\:|\hspace{0.5in}|\;| $$$
$$ T\!\!\!\!\!X\hspace{0.5in}|\,|\hspace{0.5in}|\:|\hspace{0.5in}|\;| $$
Single dot, commonly used to indicate a product, is written with \cdot:
$$ \vec{a} = \vec{b}\cdot\vec{c} $$$
$$ \vec{a} = \vec{b}\cdot\vec{c} $$
Horizontal dots: both at the bottom of the line, \ldots, or centered about it, \cdots:
$$ x = \{1, 2, \ldots, n\} \hspace{1.0in} x! = 1 \times 2 \times \cdots \times n $$$
$$ x = \{1, 2, \ldots, n\} \hspace{1.0in} x! = 1 \times 2 \times \cdots \times n $$
Diagonal and vertical dots: written with \ddots and \vdots, are useful for writing matrices:
$$
I = \left|
\begin{array}{ccc}
1 & \cdots & 0\\
\vdots & \ddots & \vdots\\
0 & \cdots & 1
\end{array}
\right|
$$$
$$
I = \left|
\begin{array}{ccc}
1 & \cdots & 0\\
\vdots & \ddots & \vdots\\
0 & \cdots & 1
\end{array}
\right|
$$
Usually lines are separated by \\ but in some forums, lines are separated by \\\ or even \\\\.
Superscripts and subcripts
superscripts:
$$a^n \hspace{0.5in} a^n+1 \hspace{0.5in} a^{n+1} \hspace{0.5in} a^{{n+1}^2}$$$
$$a^n \hspace{0.5in} a^n+1 \hspace{0.5in} a^{n+1} \hspace{0.5in} a^{{n+1}^2}$$
subscripts:
$$a_k \hspace{0.5in} a_k+1 \hspace{0.5in} a_{k+1} \hspace{0.5in} a^{{k+1}^2}$$$
$$a_k \hspace{0.5in} a_k+1 \hspace{0.5in} a_{k+1} \hspace{0.5in} a^{{k+1}^2}$$
both:
$$a^n_k \hspace{0.5in} ^2R_3$$$
$$a^n_k \hspace{0.5in} ^2R_3$$
as inline bounds:
\( \sum_{i=0}^{n}i \times \prod_{j=1}^{k}{j} \approx \int_{0}^{n}x dx \)
$%\sum_{i=0}^{n}i \times \prod_{j=1}^{k}{j} \approx \int_{0}^{n}x dx$%
as own-line bounds:
$$\sum_{i=0}^{n}i \times \prod_{j=1}^{k}{j} \approx \int_{0}^{n}x dx$$$
$$\sum_{i=0}^{n}i \times \prod_{j=1}^{k}{j} \approx \int_{0}^{n}x dx$$
Fractions, binomials and roots
Fractions:
$$ f(x) = \frac{1}{2} \frac{1}{1 + \frac{1}{n}} $$$
$$ f(x) = \frac{1}{2} \frac{1}{1 + \frac{1}{n}} $$
Binomial coefficient:
$$\binom{n}{k} = \frac{n!}{k!(n-k)!}$$$
$$\binom{n}{k} =\frac{n!}{k!(n-k)!}$$
Roots:
$$ \sqrt{4} = 2 \hspace{0.5in} \sqrt[3]{8} = 2 \hspace{0.5in} $$$
$$ \sqrt{4} = 2 \hspace{0.5in} \sqrt[3]{8} = 2 \hspace{0.5in} $$
Limits, integrals and derivatives
limits:
$$ \lim_{n \rightarrow \infty} \frac{1}{n} = 0 $$$
$$ \lim_{n \rightarrow \infty} \frac{1}{n} = 0 $$
Integrals
$$ f(x) = \int_{a}^{b} x^2 dx \hspace{0.5in} \oint_{L} f(x) dx$$$
$$ f(x) = \int_{a}^{b} x^2 dx \hspace{0.5in} \oint_{L} f(x) dx$$
Derivatives and partial derivatives
$$ \frac{dx}{dt} = \dot{x} \hspace{0.5in} \frac{\partial^2 f}{\partial x \partial y} = g(x)$$$
$$ \frac{dx}{dt} = \dot{x} \hspace{0.5in}
\frac{\partial^2 f}{\partial x \partial y} = g(x)$$
Multi-line equations
We can think of them as two-column tables: we align the equal sign using an ampersand and we separate the lines with \\:
$$
\begin{align}
F(x) & = 1 + x + \frac{x^2}{2!} + \frac{x^3}{3!} + \cdots \\
& = \exp(x)
\end{align}
$$$
$$
\begin{align}
F(x) & = 1 + x + \frac{x^2}{2!} + \frac{x^3}{3!} + \cdots \\
& = \exp(x)
\end{align}
$$
Usually lines are separated by \\ but in some forums, lines are separated by \\\ or even \\\\.
Delimiters and Function definitions
Delimiters
These are characters that, like parenthesis or brackets, surround a block of text. They always come in pairs: an opening delimiter and a closing one:
$$
\begin{array}{lllllllllll}
( & \mbox{(} & \hspace{.4in} &
) & \mbox{)} & \hspace{.8in} &
[ & \mbox{]} & \hspace{.4in} &
] & \mbox{]}\\
\{ & \mbox{\{} & \hspace{.4in} &
\} & \mbox{\}} & \hspace{.8in} &
\lfloor & \mbox{\lfloor} & \hspace{.4in} &
\rfloor & \mbox{\rfloor}\\
\lceil & \mbox{\lceil} & \hspace{.4in} &
\rceil & \mbox{\rceil} & \hspace{.8in} &
\langle & \mbox{\langle} & \hspace{.4in} &
\rangle & \mbox{\rangle}
\end{array}
$$
Notice that the curly bracket is a special character in LaTeX (it is used to indicate the arguments of a command) and thus we have to escape it with a backslash, i.e., \{ and \}.
Resizing
Delimiters work with single-line expressions. For multi-line expressions, we can adjust the size of the delimiters with the commands \big, \Big, \bigg, and \Bigg.
$$
F = \Bigg( \big[ K \big] + \bigg\lceil \frac{a}{b} \bigg\rceil \Bigg)
$$$
$$
F = \Bigg( \big[ K \big] + \bigg\lceil \frac{a}{b} \bigg\rceil \Bigg)
$$
Function definitions
In the following example, we use delimiters – curly braces – to write the Ackermann function. Since we only need the left curly brace we use an invisible delimiter, the period, as the closing delimiter. The size of the delimiter adapts to the size of the block.
$$
A(m,n,1) = \left\{
\begin{array}{ll}
n+1 & \mbox{if } m = 0 \\
A(m-1,1) & \mbox{if } m > n \mbox{ and } n = 0\\
A(m-1, A(m,n-1)) & \mbox{if } m > 0 \mbox{ and } n > 0
\end{array}
\right.
$$$
$$
A(m,n,1) = \left\{
\begin{array}{ll}
n+1 & \mbox{if } m = 0 \\
A(m-1,1) & \mbox{if } m > n \mbox{ and } n = 0\\
A(m-1, A(m,n-1)) & \mbox{if } m > 0 \mbox{ and } n > 0
\end{array}
\right.
$$
Usually lines are separated by \\ but in some forums, lines are separated by \\\ or even \\\\.
Vectors and matrices
Vectors
$$^i\vec{P}_j(a) = \left| \begin{array}{cccc}a & b & c & d \end{array} \right|^T$$$
$$^i\vec{P}_j(a) = \left| \begin{array}{cccc}a & b & c & d \end{array} \right|^T$$
matrices
$$
I = \left|
\begin{array}{ccc}
1 & 0 & 0\\
0 & 1 & 0\\
0 & 0 & 1
\end{array}
\right|
$$$
$$ I = \left|
\begin{array}{ccc}
1 & 0 & 0\\
0 & 1 & 0\\
0 & 0 & 1
\end{array}
\right|
$$
Usually lines are separated by \\ but in some forums, lines are separated by \\\ or even \\\\.
Calligraphic type
LaTeX provides a calligraphic type only for the uppercase letters:
$$
\begin{array}{llllllllllllll}
\cal A & \mbox{\cal A} & \hspace{.15in} &
\cal B & \mbox{\cal B} & \hspace{.15in} &
\cal C & \mbox{\cal C} & \hspace{.15in} &
\cal D & \mbox{\cal D} & \hspace{.15in} &
\cal E & \mbox{\cal E}\\
\cal F & \mbox{\cal F} & \hspace{.15in} &
\cal G & \mbox{\cal G} & \hspace{.15in} &
\cal H & \mbox{\cal H} & \hspace{.15in} &
\cal I & \mbox{\cal I} & \hspace{.15in} &
\cal J & \mbox{\cal J}\\
\cal K & \mbox{\cal K} & \hspace{.15in} &
\cal L & \mbox{\cal L} & \hspace{.15in} &
\cal M & \mbox{\cal M} & \hspace{.15in} &
\cal N & \mbox{\cal N} & \hspace{.15in} &
\cal O & \mbox{\cal O}\\
\cal P & \mbox{\cal P} & \hspace{.15in} &
\cal Q & \mbox{\cal Q} & \hspace{.15in} &
\cal R & \mbox{\cal R} & \hspace{.15in} &
\cal S & \mbox{\cal S} & \hspace{.15in} &
\cal T & \mbox{\cal T}\\
\cal U & \mbox{\cal U} & \hspace{.15in} &
\cal V & \mbox{\cal V} & \hspace{.15in} &
\cal W & \mbox{\cal W} & \hspace{.15in} &
\cal X & \mbox{\cal X} & \hspace{.15in} &
\cal Y & \mbox{\cal Y}\\
\cal Z & \mbox{\cal Z} & \hspace{.15in} &
& & \hspace{.15in} &
& & \hspace{.15in} &
& & \hspace{.15in} &
&
\end{array}
$$
For example:
..and let \({\cal X} = {\cal A} \cup {\cal B}\) be the space..
..and let \({\cal X} = {\cal A} \cup {\cal B}\) be the space..
Math accents
$$
\begin{array}{lllllllllll}
\hat{a} & \mbox{\hat{a}} & \hspace{.4in} &
\acute{a} & \mbox{\acute{a}} & \hspace{.4in} &
\bar{a} & \mbox{\bar{a}} & \hspace{.4in} &
\dot{a} & \mbox{\dot{a}}\\
\check{a} & \mbox{\check{a}} & \hspace{.4in} &
\grave{a} & \mbox{\grave{a}} & \hspace{.4in} &
\vec{a} & \mbox{\vec{a}} & \hspace{.4in} &
\ddot{a} & \mbox{\ddot{a}}\\
\breve{a} & \mbox{\breve{a}} & \hspace{.4in} &
\tilde{a} & \mbox{\tilde{a}} & \hspace{.4in} &
& & \hspace{.4in} &
&
\end{array}
$$
For example:
\(Andr\acute{e}\!s\;Casta\tilde{n}o \hspace{0.5in} \ddot{x}=\frac{d \dot{x}}{dt}\)
\(Andr\acute{e}\!s\;Casta\tilde{n}o \hspace{0.5in} \ddot{x}=\frac{d \dot{x}}{dt}\)
although, if the accent is not going to be applied to a math symbol, it is much easier to write it using the standard character modifier and the \mbox command:
\(\mbox{Andrés Castaño}\)
\(\mbox{Andrés Castaño}\)
Over and underlining
The \hat and the \tilde commands have wide versions – \widehat and \widetilde – that try to accommodate large arguments:
$$\widetilde{a + b} \hspace{0.5in} \widehat{a + b}$$$
$$\widetilde{a + b} \hspace{0.5in} \widehat{a + b}$$
A more common type of over-lining uses the \overline command,
$$ \overline{A \cdot B} \; = \overline{A} \; + \overline{B} $$$
$$ \overline{A \cdot B} \; = \overline{A} \; + \overline{B} $$
or an over- or under-brace,
$$ \overbrace{1, 2, \underbrace{3, \ldots, 99}_{97}, 100}^{100}$$$
$$ \overbrace{1, 2, \underbrace{3, \ldots, 99}_{97}, 100}^{100}$$
Greek alphabet
$$
\begin{array}{lllllllllll}
\alpha & \mbox{\alpha} & \hspace{.2in} &
\theta & \mbox{\theta} & \hspace{.2in} &
o & \mbox{o} & \hspace{.2in} &
\tau & \mbox{\tau}\\
\beta & \mbox{\beta} & \hspace{.2in} &
\vartheta & \mbox{\vartheta} & \hspace{.2in} &
\pi & \mbox{\pi} & \hspace{.2in} &
\upsilon & \mbox{\upsilon}\\
\gamma & \mbox{\gamma} & \hspace{.2in} &
\iota & \mbox{\iota} & \hspace{.2in} &
\varpi & \mbox{\varpi} & \hspace{.2in} &
\phi & \mbox{\phi}\\
\delta & \mbox{\delta} & \hspace{.2in} &
\kappa & \mbox{\kappa} & \hspace{.2in} &
\rho & \mbox{\rho} & \hspace{.2in} &
\varphi & \mbox{\varphi}\\
\epsilon & \mbox{\epsilon} & \hspace{.2in} &
\lambda & \mbox{\lambda} & \hspace{.2in} &
\varrho & \mbox{\varrho} & \hspace{.2in} &
\chi & \mbox{\chi}\\
\varepsilon & \mbox{\varepsilon} & \hspace{.2in} &
\mu & \mbox{\mu} & \hspace{.2in} &
\sigma & \mbox{\sigma} & \hspace{.2in} &
\psi & \mbox{\psi}\\
\zeta & \mbox{\zeta} & \hspace{.2in} &
\nu & \mbox{\nu} & \hspace{.2in} &
\varsigma & \mbox{\varsigma} & \hspace{.2in} &
\omega & \mbox{\omega}\\
\eta & \mbox{\eta} & \hspace{.2in} &
\xi & \mbox{\xi} & \hspace{.2in} &
& & \hspace{.2in} &
& \\
\Gamma & \mbox{\Gamma} & \hspace{.2in} &
\Lambda & \mbox{\Lambda} & \hspace{.2in} &
\Sigma & \mbox{\Sigma} & \hspace{.2in} &
\Psi & \mbox{\Psi}\\
\Delta & \mbox{\Delta} & \hspace{.2in} &
\Xi & \mbox{\Xi} & \hspace{.2in} &
\Upsilon & \mbox{\Upsilon} & \hspace{.2in} &
\Omega & \mbox{\Omega}\\
\Theta & \mbox{\Theta} & \hspace{.2in} &
\Pi & \mbox{\Pi} & \hspace{.2in} &
\Phi & \mbox{\Phi} & \hspace{.2in} &
&
\end{array}
$$
Operation symbols
$$
\begin{array}{lllllllllll}
\pm & \mbox{\pm} & \hspace{.2in} &
\cap & \mbox{\cap} & \hspace{.2in} &
\diamond & \mbox{\diamond} & \hspace{.2in} &
\oplus & \mbox{\oplus}\\
\mp & \mbox{\mp} & \hspace{.2in} &
\cup & \mbox{\cup} & \hspace{.2in} &
\bigtriangleup & \mbox{\bigtriangleup} & \hspace{.2in} &
\ominus & \mbox{\ominus}\\
\times & \mbox{\times} & \hspace{.2in} &
\uplus & \mbox{\uplus} & \hspace{.2in} &
\bigtriangledown & \mbox{\bigtriangleudown} & \hspace{.2in} &
\otimes & \mbox{\otimes}\\
\div & \mbox{\div} & \hspace{.2in} &
\sqcap & \mbox{\sqcap} & \hspace{.2in} &
\triangleleft & \mbox{\triangleleft} & \hspace{.2in} &
\oslash & \mbox{\\oslash}\\
\ast & \mbox{\ast} & \hspace{.2in} &
\sqcup & \mbox{\sqcup} & \hspace{.2in} &
\triangleright & \mbox{\triangleright} & \hspace{.2in} &
\odot & \mbox{\\odot}\\
\star & \mbox{\star} & \hspace{.2in} &
\vee & \mbox{\vee} & \hspace{.2in} &
\lhd & \mbox{\lhd} & \hspace{.2in} &
\bigcirc & \mbox{\\bigcirc}\\
\circ & \mbox{\circ} & \hspace{.2in} &
\wedge & \mbox{\wedge} & \hspace{.2in} &
\rhd & \mbox{\rhd} & \hspace{.2in} &
\dagger & \mbox{\dagger}\\
\bullet & \mbox{\bullet} & \hspace{.2in} &
\setminus & \mbox{\setminus} & \hspace{.2in} &
\unlhd & \mbox{\unlhd} & \hspace{.2in} &
\ddagger & \mbox{\ddagger}\\
\cdot & \mbox{\cdot} & \hspace{.2in} &
\wr & \mbox{\wr} & \hspace{.2in} &
\unrhd & \mbox{\unrhd} & \hspace{.2in} &
\amalg & \mbox{\amalg}
\end{array}
$$
Relation symbols
To cross out any of these symbols, we use the command \not:
\(x \not\lt y\)
\(x \not\lt y\)
$$
\begin{array}{lllllllllll}
\leq & \mbox{\leq} & \hspace{.2in} &
\geq & \mbox{\geq} & \hspace{.2in} &
\equiv & \mbox{\equiv} & \hspace{.2in} &
\models & \mbox{\models}\\
\prec & \mbox{\prec} & \hspace{.2in} &
\succ & \mbox{\succ} & \hspace{.2in} &
\sim & \mbox{\sim} & \hspace{.2in} &
\perp & \mbox{\perp}\\
\preceq & \mbox{\preceq} & \hspace{.2in} &
\succeq & \mbox{\succeq} & \hspace{.2in} &
\simeq & \mbox{\simeq} & \hspace{.2in} &
\mid & \mbox{\mid}\\
\ll & \mbox{\ll} & \hspace{.2in} &
\gg & \mbox{\gg} & \hspace{.2in} &
\asymp & \mbox{\asymp} & \hspace{.2in} &
\parallel & \mbox{\parallel}\\
\subset & \mbox{\subset} & \hspace{.2in} &
\supset & \mbox{\supset} & \hspace{.2in} &
\approx & \mbox{\approx} & \hspace{.2in} &
\bowtie & \mbox{\bowtie}\\
\subseteq & \mbox{\subseteq} & \hspace{.2in} &
\supseteq & \mbox{\supseteq} & \hspace{.2in} &
\cong & \mbox{\cong} & \hspace{.2in} &
\Join & \mbox{\Join}\\
\sqsubset & \mbox{\sqsubset} & \hspace{.2in} &
\sqsupset & \mbox{\sqsupset} & \hspace{.2in} &
\neq & \mbox{\neq} & \hspace{.2in} &
\smile & \mbox{\smile}\\
\sqsubseteq & \mbox{\sqsubseteq} & \hspace{.2in} &
\sqsupseteq & \mbox{\sqsupseteq} & \hspace{.2in} &
\doteq & \mbox{\doteq} & \hspace{.2in} &
\frown & \mbox{\frown}\\
\in & \mbox{\in} & \hspace{.2in} &
\ni & \mbox{\ni} & \hspace{.2in} &
\propto & \mbox{\propto} & \hspace{.2in} &
& \\
\vdash & \mbox{\vdash} & \hspace{.2in} &
\dashv & \mbox{\dashv} & \hspace{.2in} &
& & &
& \\
\end{array}
$$
Arrows
$$
\begin{array}{llllllll}
\leftarrow & \mbox{\leftarrow} & \hspace{.01in} &
\longleftarrow & \mbox{\longleftarrow} & \hspace{.01in} &
\uparrow & \mbox{\uparrow}\\
\Leftarrow & \mbox{\Leftarrow} & \hspace{.01in} &
\Longleftarrow & \mbox{\Longleftarrow} & \hspace{.01in} &
\Uparrow & \mbox{\Uparrow}\\
\rightarrow & \mbox{\rightarrow} & \hspace{.01in} &
\longrightarrow & \mbox{\longrightarrow} & \hspace{.01in} &
\downarrow & \mbox{\downarrow}\\
\Rightarrow & \mbox{\Rightarrow} & \hspace{.01in} &
\Longrightarrow & \mbox{\Longrightarrow} & \hspace{.01in} &
\Downarrow & \mbox{\Downarrow}\\
\leftrightarrow & \mbox{\leftrightarrow} & \hspace{.01in} &
\longleftrightarrow & \mbox{\longleftrightarrow} & \hspace{.01in} &
\updownarrow & \mbox{\updownarrow}\\
\Leftrightarrow & \mbox{\Leftrightarrow} & \hspace{.01in} &
\Longleftrightarrow & \mbox{\Longleftrightarrow} & \hspace{.01in} &
\Updownarrow & \mbox{\Updownarrow}\\
\mapsto & \mbox{\mapsto} & \hspace{.01in} &
\longmapsto & \mbox{\longmapsto} & \hspace{.01in} &
\nearrow & \mbox{\nearrow}\\
\hookleftarrow & \mbox{\hookleftarrow} & \hspace{.01in} &
\hookrightarrow & \mbox{\hookrightarrow} & \hspace{.01in} &
\searrow & \mbox{\searrow}\\
\leftharpoonup & \mbox{\leftharpoonup} & \hspace{.01in} &
\rightharpoonup & \mbox{\rightharpoonup} & \hspace{.01in} &
\swarrow & \mbox{\swarrow}\\
\leftharpoondown & \mbox{\leftharpoondown} & \hspace{.01in} &
\rightharpoondown & \mbox{\rightharpoondown} & \hspace{.01in} &
\nwarrow & \mbox{\nwarrow}\\
\rightleftharpoons & \mbox{\rightleftharpoons} & \hspace{.01in} &
\leadsto & \mbox{\leadsto} & \hspace{.01in} &
&
\end{array}
$$
Miscellaneous Symbols
$$
\begin{array}{lllllllllll}
\aleph & \mbox{\aleph} & \hspace{.2in} &
\prime & \mbox{\prime} & \hspace{.2in} &
\forall & \mbox{\forall} & \hspace{.2in} &
\infty & \mbox{\infty}\\
\hbar & \mbox{\hbar} & \hspace{.2in} &
\emptyset & \mbox{\emptyset} & \hspace{.2in} &
\exists & \mbox{\exists} & \hspace{.2in} &
\Box & \mbox{\Box}\\
\imath & \mbox{\imath} & \hspace{.2in} &
\nabla & \mbox{\nabla} & \hspace{.2in} &
\neg & \mbox{\neg} & \hspace{.2in} &
\Diamond & \mbox{\Diamond}\\
\jmath & \mbox{\jmath} & \hspace{.2in} &
\surd & \mbox{\surd} & \hspace{.2in} &
\flat & \mbox{\flat} & \hspace{.2in} &
\triangle & \mbox{\triangle}\\
\ell & \mbox{\ell} & \hspace{.2in} &
\top & \mbox{\top} & \hspace{.2in} &
\natural & \mbox{\natural} & \hspace{.2in} &
\clubsuit & \mbox{\clubsuit}\\
\wp & \mbox{\wp} & \hspace{.2in} &
\bot & \mbox{\bot} & \hspace{.2in} &
\sharp & \mbox{\sharp} & \hspace{.2in} &
\diamondsuit & \mbox{\diamondsuit}\\
\Re & \mbox{\Re} & \hspace{.2in} &
\| & \mbox{\|} & \hspace{.2in} &
\backslash & \mbox{\backslash} & \hspace{.2in} &
\heartsuit & \mbox{\heartsuit}\\
\Im & \mbox{\Im} & \hspace{.2in} &
\angle & \mbox{\angle} & \hspace{.2in} &
\partial & \mbox{\partial} & \hspace{.2in} &
\spadesuit & \mbox{\spadesuit}\\
\mho & \mbox{\mho} & \hspace{.2in} &
& & \hspace{.2in} &
& & \hspace{.2in} &
&
\end{array}
$$
Variable-size symbols
$$
\begin{array}{llllllll}
\sum & \mbox{\sum} & \hspace{.3in} &
\bigcap & \mbox{\bigcap} & \hspace{.3in} &
\bigodot & \mbox{\bigodot}\\
\prod & \mbox{\prod} & \hspace{.3in} &
\bigcup & \mbox{\bigcup} & \hspace{.3in} &
\bigotimes & \mbox{\bigotimes}\\
\coprod & \mbox{\coprod} & \hspace{.3in} &
\bigsqcup & \mbox{\bigsqcup} & \hspace{.3in} &
\bigoplus & \mbox{\bigoplus}\\
\int & \mbox{\int} & \hspace{.3in} &
\bigvee & \mbox{\bigvee} & \hspace{.3in} &
\biguplus & \mbox{\biguplus}\\
\oint & \mbox{\oint} & \hspace{.3in} &
\bigwedge & \mbox{\bigwedge} & \hspace{.3in} &
&
\end{array}
$$
Good luck
LaTeX Symbols
This post is an extended version of the following original post:
Title: Adding $%\LaTeX$% (and highlighting, color and math) to your posts
Forum of “Introduction to Computer Science”, by David Evans, offered at Udacity
First publication date: 22 Jul, 2012, 23:05 PST
Last updated: 13 Sep, 2019, 10:54 PST
Link: http://forums.udacity.com/cs101/questions/17565/adding-latex-and-highlighting-colorbluecolor-and-malphatau-h-to-your-posts; this post might still be reachable using a Udacity account but it is no longer public; I posted it using the screenname ‘Goldsong’.