# LaTeX/Math jokes [closed]

Lighten up a bit guys. How about the following

\documentclass{article}
\usepackage{graphicx}
\begin{document}
If~~$\displaystyle\lim_{x\rightarrow8}\frac{1}{x{-}8}=\infty$
~~then~~$\displaystyle\lim_{x\rightarrow5}\frac{1}{x{-}5}=\rotatebox{90}{5}$
\end{document}


Which gives —

Can anyone give me some nice Tikz of PStricks code for the following

I am sure there there must be more Latex humor out there, even among the Germans ;-)

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## closed as not constructive by Caramdir, Lev Bishop, lockstep, Loop Space, JakeMay 29 '11 at 20:23

As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance.If this question can be reworded to fit the rules in the help center, please edit the question.

I made it CW because it asks about more contributions which wouldn't fit in the normal Q&A scheme. –  Martin Scharrer May 16 '11 at 7:21
@Danie: You should add any new examples that you think of as answers rather than editing the question. –  Loop Space May 16 '11 at 8:41
1+1=3 for sufficient large 1s and sufficient small 3s. –  Martin Scharrer May 16 '11 at 10:55
I've also voted to close now. The idea I had was that the "jokes" should reveal something about TeX, such as illustrating a technique. Some answers did that, but the longer the question stays open then the less likely it is that new answers will continue in that vein. So while I enjoyed it when it was asked, I think that it had a finite life and it is now time to close it. –  Loop Space May 29 '11 at 20:21
Code and Output –  In PSTricks we trust Aug 10 '12 at 6:36

\font\donteveruseoutsidecartoons="Comic Sans MS" at 14pt
\font\donteveruseoutsidecartoonstwo="Comic Sans MS/IB:slant=.3pt" at 22pt
\input tikz
\usetikzlibrary{shapes.callouts,positioning}
\tikzpicture[mycallout/.style={draw,ellipse callout,inner sep=1.2ex,
callout relative pointer={#1}}]
\node[mycallout={(.5cm,-.5cm)}] (ico) {\donteveruseoutsidecartoons Be rational};
\node[mycallout={(-.5cm,-.5cm)}, right=of ico] (pco) {\donteveruseoutsidecartoons Get real};
\node[below=.1ex of ico.pointer] {\donteveruseoutsidecartoonstwo i};
\node[below left=.1ex of pco.pointer] {\donteveruseoutsidecartoonstwo π\vphantom(};
\endtikzpicture
\bye


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especially for the font names –  Loop Space May 16 '11 at 7:40
This is very good. People may not realize it, but all this stuff is very usefull to make boring engineering or math lectures a little bit more interesting. –  Danie Els May 16 '11 at 8:00
@Danie: Completely agree. And often (speaking as a lecturer) it's not until I see an example that I realise that such things are possible so there is certainly potential value in this question. –  Loop Space May 16 '11 at 8:28
–1 for the font. ;-) –  Konrad Rudolph May 16 '11 at 11:53
@Konrad --- surely that should be \mathrm{e}^{\mathrm{i}\pi} for the font? –  Ian Thompson May 16 '11 at 15:59
\documentclass{article}
\usepackage{amsmath}

\begin{document}

Expand $(a+b)^n$:
\begin{gather*}
(a + b)^n\\
(a\ + \ b)^n\\
\end{gather*}

\end{document}


EDIT: to Andrew:

\documentclass{article}

\newcount\mycntr

\begin{document}

Expand $(a+b)^n$:

\begin{center}
\mycntr=0
\ifnum\mycntr<40
$(a\hskip\mycntr pt +\hskip\mycntr pt b)^n$\\
\repeat
\end{center}

\end{document}

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This one is epic. –  Paulo Cereda May 16 '11 at 16:31
Aw, come on ... no iteration? Let's have a more programmatic version of this one! –  Loop Space May 16 '11 at 17:45
@Andrew Stacey: done. Personally I prefer the non-iterative version. –  Gonzalo Medina May 16 '11 at 18:09
I prefer expanding the expression in 2 dimension. –  xport May 27 '11 at 7:05

\documentclass[a4paper,12pt]{article}
\usepackage[margin=1in]{geometry}

\usepackage{graphicx}
\usepackage{pgffor}
\pagestyle{empty}

\parindent=0pt
\begin{document}
\large\sffamily

\resizebox{\textwidth}{!}{The first 500 natural random numbers}

\vspace{1em}

\centerline{\LARGE For easy access listed in their natural order}
\bigskip

\par\noindent
\foreach \n in {1,...,500} {%
\makebox[1.8em][r]{\n}
}

\end{document}

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@ Martin Scharrer - I like this. Do you mind if I turn it into a natural number spotter's guide and stick it on wall? –  Richard Terrett May 18 '11 at 8:29
@Richard: Sure. Note I didn't came up with it. I saw this in my college in the math building once. –  Martin Scharrer May 18 '11 at 8:32

A silly one I found on a blog:

\documentclass{article}
\usepackage{graphicx}
\usepackage{cancel}

\begin{document}

\begin{eqnarray*}
\frac{1}{n}\sin x & = & \mathrm{?} \\
\frac{1}{\cancel{n}} \mathrm{si}\cancel{\mathrm{n}} ~x & = & \mathrm{?} \\
\mathrm{six} & = & 6
\end{eqnarray*}

\end{document}


This one from xkcd is a classic:

\documentclass{article}
\usepackage{graphicx}
\usepackage{amsmath}

\begin{document}

$\begin{bmatrix} \cos 90^{\circ} & \sin 90^{\circ}\\ -\sin 90^{\circ} & \cos 90^{\circ} \end{bmatrix} \begin{bmatrix} a1 \\ a2 \end{bmatrix} =$
\rotatebox[origin=c]{270}{$\begin{bmatrix} a1 \\ a2 \end{bmatrix}$}

\end{document}

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I never played with tikz before, so that's my first attempt. I simply love the following joke:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{decorations.pathmorphing}
\usepackage{frcursive}
\begin{document}

Find $x$.

\begin{tikzpicture}
\draw (0,0) -- (4,0) node[midway,below] {4 cm}
-- (4,3) node[midway,right] {3 cm}
-- (0,0) node[midway,left,circle,draw=blue,decorate,decoration={random steps,segment length=1pt,amplitude=0.5pt}]{$x$}
-- (4,0) rectangle (3.7,0.3)
-- cycle;
\draw (0.4,0) arc (0:30:0.5);
\draw (4,2.6) arc (270:226:0.5);
\draw (1,2.1) node []{\color{blue}\fontfamily{frc}\selectfont{It's here!}};
\end{tikzpicture}

\end{document}


The result:

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You should also draw a blue circle around x. Just add circle,draw=blue to its node. I might need to set the color of the content back to black. –  Martin Scharrer May 16 '11 at 15:22
@Martin Scharrer: Thanks a lot, I updated both code and image. It looks way better that way! =) –  Paulo Cereda May 16 '11 at 15:59
The circle could use a jittering line (it’s hand-drawn, right?). You can use the random steps decoration for that. –  Konrad Rudolph May 16 '11 at 16:07
@Konrad Rudolph: Thanks, I updated the code again. You guys are awesome! =) –  Paulo Cereda May 16 '11 at 16:24
A pedant's note: you could use a \, or \SI from siunitx to typeset the lengths. –  Andrey Vihrov May 17 '11 at 15:11

Mathematicians do it in \LaTeX.

I'll get my coat.

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To all my Australian friends:

\documentclass{article}
\usepackage{graphicx}
\begin{document}
\noindent Are there any \raisebox{1ex}{\rotatebox[origin=B]{180}{Australians}}
here mate?\\ Hang on tight!
\end{document}


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Here's another joke I remember:

\documentclass{article}

\usepackage[T1]{fontenc}
\usepackage[light,math]{anttor}

\begin{document}

Let $\displaystyle f(a) = \sqrt[n]{e^x}$.

\begin{minipage}{0.5\textwidth}
\begin{eqnarray*}
\lim_{t\rightarrow\infty} f(a) - \frac{i}{f(t)} & = & \frac{d}{dx} f(u) \\
\lim_{t\rightarrow\infty} f(a) - \frac{i}{\infty} & = & \frac{d}{dx} f(u) \\
\lim_{t\rightarrow\infty} f(a) - 0 & = & \frac{d}{dx} f(u)
\end{eqnarray*}
\end{minipage}

\bigskip

Then

\begin{minipage}{0.5\textwidth}
\begin{eqnarray*}
\sqrt[n]{e^x} & = & \frac{d}{dx} f(u) \\
(\sqrt[n]{e^x})^n & = & \frac{d}{dx} f(u)^n \\
e^x & = & \frac{d}{dx} f(u)^n \\
\int e^x & = & f(u)^n
\end{eqnarray*}
\end{minipage}

\end{document}


The output:

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You deliberately made many typos? –  xport May 27 '11 at 7:07
Sadly, no. I simply wrote it as it is from a PNG image. =) –  Paulo Cereda May 27 '11 at 9:11

Riffing on the "Australians" joke, borrowing from this answer.

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I get the original joke, but fail to see it in the alternations. –  Martin Scharrer May 16 '11 at 11:31
@Martin it's my tribute to Stewart Lee –  Seamus May 16 '11 at 11:40