FIRSTwiki:TeX help

From FIRSTwiki

As of June 2004, we have TeX markup for mathematical formulas on Wikipedia. It generates either PNG images or simple HTML markup, depending on user prefs and the complexity of the expression. In the future, as more browsers are smarter, it will be able to generate enhanced HTML or even MathML in many cases.

Math markup goes inside <math> ... </math>. Line breaks within these tags are fine, and aren't rendered. They're a good idea to keep the raw markup clear (for instance, a line break after each term or row of a matrix).

Discussion, bug reports and feature requests should go to the Wikitech-l mailing list or to TeX requests .

For style issues regarding the typesetting of math, see WikiProject Mathematics . In particular, please avoid using this feature as part of a line of regular text, as the formulas don't align properly and the font is too large.

Regarding color, notice that this page is a special page (its name begins with "FIRSTwiki:") and therefore when using some skins it has a yellow background. Normal FIRSTwiki pages are white, just like the formulas, so don't worry

1 Special characters
2 Subscripts, superscripts
3 Fractions, matrices, multilines
4 Fonts
5 Parenthesizing big expressions
6 Spacing
7 Forced PNG rendering
8 See also
9 External links

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Special characters

Feature	Syntax	How it looks rendered
std. functions (good)	\sin x + \ln y +\operatorname{sgn} z	$\sin x + \ln y +\operatorname{sgn} z$
std. functions (wrong)	sin x + ln y + sgn z	$sin x + ln y + sgn z\,$
Modular arithm.	s_k \equiv 0 \pmod{m}	$s_k \equiv 0 \pmod{m}$
Derivatives	\nabla \partial dx	$\nabla \partial dx$
Sets	\forall x\not\in\empty\subseteq A\cap B\cup \exists \{x,y\} \times C	$\forall x \not\in \empty \subseteq A\cap B\cup \exists \{x,y\} \times C$
Logic	p\wedge \bar{q} \rightarrow p\vee \bar{q} \Rightarrow \Leftrightarrow	$p\wedge \bar{q} \rightarrow p\vee \bar{q} \Rightarrow \Leftrightarrow$
Root	\sqrt{2}\approx 1.4	$\sqrt{2}\approx 1.4$
Root	\sqrt[n]{x}	$\sqrt[n]{x}$
Relations	\sim \simeq \cong \le \ge \equiv \approx \ne	$\sim \ \simeq \ \cong \ \le \ \ge \ \equiv \ \approx \ \ne$
Geometric	\angle \perp \\|	$\angle \perp \\|$
Special	\oplus \otimes \pm \mp \hbar \dagger \ddagger \star \circ \cdot \bullet \infty \vdash \models	$\oplus \otimes \pm \mp \hbar \dagger \ddagger \star \circ \cdot \bullet\ \infty \vdash\ \models$

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Subscripts, superscripts

Feature	Syntax	How it looks rendered
Superscript	a^2	$a 2$
Subscript	a_2	$a 2$
Grouping	a^{2+2}	$a 2 + 2$
Grouping	a_{i,j}	$a i, j$
Combining sub & super	x_2^3	$x_2^3$
Derivative (good)	x'	$x'$
Derivative (wrong in HTML)	x^\prime	$x^\prime$
Derivative (wrong in PNG)	x\prime	$x\prime$
Sum	\sum_{k=1}^N k^2	$\sum_{k=1}^N k^2$
Product	\prod_{i=1}^N x_i	$\prod_{i=1}^N x_i$
Limit	\lim_{n \to \infty}x_n	$\lim_{n \to \infty}x_n$
Integral	\int_{-N}^{N} e^x\, dx	$\int_{-N}^{N} e^x\, dx$
Line Integral	\oint_{C} x^3\, dx + 4y^2\, dy	$\oint_{C} x^3\, dx + 4y^2\, dy$

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Fractions, matrices, multilines

Feature

Syntax

How it looks rendered

Fractions

\frac{2}{4} or {2 \over 4}

$\frac{2}{4}$

Binomial coefficients

\binom{n}{k} or {n \choose k}

${n \choose k}$

Matrices

\begin{pmatrix} x & y \\ z & v \end{pmatrix}

$\begin{pmatrix} x & y \\ z & v \end{pmatrix}$

\begin{bmatrix} 0 & \cdots & 0 \\ \vdots &

\ddots & \vdots \\ 0 & \cdots &

0\end{bmatrix}

$\begin{bmatrix} 0 & \cdots & 0 \\ \vdots & \ddots & \vdots \\ 0 & \cdots & 0\end{bmatrix}$

\begin{Bmatrix} x & y \\ z & v \end{Bmatrix}

$\begin{Bmatrix} x & y \\ z & v \end{Bmatrix}$

\begin{vmatrix} x & y \\ z & v \end{vmatrix}

$\begin{vmatrix} x & y \\ z & v \end{vmatrix}$

\begin{Vmatrix} x & y \\ z & v \end{Vmatrix}

$\begin{Vmatrix} x & y \\ z & v \end{Vmatrix}$

\begin{matrix} x & y \\ z & v \end{matrix}

$\begin{matrix} x & y \\ z & v \end{matrix}$

Case distinctions

f(n)=\left\{\begin{matrix} n/2, & \mbox{if }n\mbox{ is

even} \\ 3n+1, & \mbox{if }n\mbox{ is odd}

\end{matrix}\right.

$f(n)=\left\{\begin{matrix} n/2, & \mbox{if }n\mbox{ is even} \\ 3n+1, & \mbox{if }n\mbox{ is odd} \end{matrix}\right.$

Multiline equations

\begin{matrix}f(n+1)&=& (n+1)^2 \\ \ & =& n^2 + 2n + 1\end{matrix}

$\begin{matrix}f(n+1)&=& (n+1)^2 \\ \ & =& n^2 + 2n + 1\end{matrix}$

Alternative multiline equations (using tables)

<table>
<tr>
<td><math>f(n+1)</math></td>
<td><math>=(n+1)^2</math></td>
</tr><tr><td></td>
<td><math>=n^2 + 2n + 1</math></td>
</tr>
</table>

$f (n + 1)$	$= (n + 1) 2$
	$= n 2 + 2 n + 1$

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Fonts

Feature	Syntax	How it looks rendered
Greek letters	\alpha \beta \gamma \Gamma \phi \Phi \Psi\ \tau \Omega	$\alpha\ \beta\ \gamma\ \Gamma\ \phi\ \Phi\ \Psi\ \tau\ \Omega$
Blackboard bold	x\in\mathbb{R}\sub\mathbb{C}	$x\in\mathbb{R}\subset\mathbb{C}$
boldface (vectors)	\mathbf{x}\cdot\mathbf{y} = 0	$\mathbf{x}\cdot\mathbf{y} = 0$
boldface (greek)	\boldsymbol{\alpha}+\boldsymbol{\beta}+\boldsymbol{\gamma}	$\boldsymbol{\alpha}+\boldsymbol{\beta}+\boldsymbol{\gamma}$
Fraktur typeface	\mathfrak{a} \mathfrak{A} \mathfrak{B}	$\mathfrak{a} \mathfrak{A} \mathfrak{B}$
Script	\mathcal{ABC}	$\mathcal{ABC}$
Hebrew	\aleph \beth \gimel \daleth	$\aleph\ \beth\ \gimel\ \daleth$
non-italicised characters	\mbox{abc}	$abc$

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Parenthesizing big expressions

Feature	Syntax	How it looks rendered
Not good	( \frac{1}{2} )	$( \frac{1}{2} )$
Better	\left( \frac{1}{2} \right)	$\left ( \frac{1}{2} \right )$

You can use various delimiters with \left and \right:

Feature	Syntax	How it looks rendered
Parentheses	\left( A \right)	$\left( A \right)$
Brackets	\left[ A \right]	$\left[ A \right]$
Braces	\left\{ A \right\}	$\left\{ A \right\}$
Angle brackets	\left\langle A \right\rangle	$\left\langle A \right\rangle$
Bars	\left\| A \right\|	$\left\| A \right\|$
Use \left. and \right. if you don't want a delimiter to appear:	\left. {A \over B} \right\} \to X	$\left. {A \over B} \right\} \to X$

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Spacing

Note that TeX handles most spacing automatically, but you may sometimes want manual control.

Feature	Syntax	How it looks rendered
double quad space	a \qquad b	$a \qquad b$
quad space	a \quad b	$a \quad b$
text space	a\ b	$a\ b$
large space	a\;b	$a\;b$
medium space	a\>b	[not supported]
small space	a\,b	$a\,b$
no space	ab	$ab\,$
negative space	a\!b	$a\!b$

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Forced PNG rendering

If you must, it is possible to force the formula to render as PNG, without affecting the display of the formula, by adding \,\! (small space and negative space, which cancel out) somewhere inside the math tags (probably at the end).

This could be useful to keep the rendering of formulas in a proof consistent, for example, or to fix formulas that render incorrectly in HTML (x prime, or a^{2+2}), or to demonstrate how something is rendered when it would normally show up as HTML (as in the examples above). For instance:

Syntax	How it looks rendered
a^{2+2}	$a 2 + 2$
a^{2+2 }	$a 2 + 2$
a^{2+2} \,\!	$a^{2+2} \,\!$
\int_{-N}^{N} e^x\, dx	$\int_{-N}^{N} e^x\, dx$
\int_{-N}^{N} e^x\, dx \,\!	$\int_{-N}^{N} e^x\, dx \,\!$