
Ask HN: Any good math jokes? - whackedspinach
I'm trying to come up with a good math joke for our math team t-shirts.  Last year we had "Know you limits, don't drink and derive."  The shirt included a fuzzy graph.<p>I'm thinking about using an xkcd comic if the author gives me permission, but the images are somewhat small for t-shirts, so I might have to throw my own together anyways.<p>Got any good ideas?
======
zck
An engineer, a physicist, and a mathematician go to a conference together, and
split a room in the hotel. They check in and go to sleep. The hotel is old
(they couldn't afford anything better on professors' salaries), so the room is
heated by a fireplace. A spark jumps out of the fire and catches the rug on
fire. The engineer smells the smoke and wakes up. He jumps out of bed, sees
the fire, and looks around. The first thing he sees is the ice bucket, so he
takes it, fills it up from the sink, and throws the water on the fire. He
drops the ice bucket next to the fireplace and goes back to bed.

The fire throws another spark, creating another fire. The physicist wakes up
and sees the fire. He calculates that, given the size of the fire, and amount
of oxygen needed to be displaced to put out a fire of said size, a glass of
water will be sufficient. He fills up his water glass from the sink, and while
running to the fire, throws the water at the fire at the exact distance from
the fire that gets the water to the fire earliest, putting it out. He drops
the glass next to the fireplace and goes to sleep.

The fire sparks once more, and the mathematician wakes up and sees the fire.
He looks at the ice bucket and glass sitting next to the fireplace, says "Aha!
A solution exists!", and goes back to bed.

It's a math joke, but not one suitable for t-shirts.

~~~
JeanPierre
While we're at jokes not suitable for t-shirts:

A mathematician, an engineer and a physicist were travelling through Scotland
when they saw a black sheep through the window of the train.

"Aha", says the engineer, "I see that Scottish sheep are black."

"Hmm", says the physician, "You mean that some Scottish sheep are black".

"Nonono", says the mathematician, "All we know is that there is at least one
sheep in Scotland, and that at least one side of that one sheep is black."

------
biju
An infinite number of mathematicians walk into a bar. The first one orders a
beer. The second orders half a beer. The third, a quarter of a beer. The
bartender says "You're all idiots", and pours two beers.

more: [http://www.metafilter.com/76377/Two-mathematicians-walk-
into...](http://www.metafilter.com/76377/Two-mathematicians-walk-into-a-bar)

~~~
mr_twj
Or its sibling: a genie grants both a mathematician and an engineer their
greatest desire to be located at the end of the room given that each step they
take towards it is half the distance than their last. The mathematician throws
his arms up and yells "Impossible! I'll never reach it," and storms out of the
room. The engineer just smiles and says to the genie, "I can get close
enough."

------
tzs
Q: What's purple and commutes? A: An Abelian grape.

Q: What's yellow and equivalent to the axiom of choice? A: Zorn's Lemon.

An engineer, a physicist, and a mathematician are riding on a train through
the countryside. They look out the window and see a black cow. The engineer
says, "Look, all the cows in this county are black!". The physicist sighs, and
says "No, at least one cow in this county is black". The mathematician shakes
his head sadly and says "There is at least one cow in this county that is
black on at least one side".

Q: Why do Jewish mathematicians prefer complex analysis over many other fields
of mathematics? A: because it is Cauchy'er.

I was never able to get this one to work out, but maybe someone smarter can do
it. There was a line in a physics book I read once that said something like
"electromagnetic fields can be described by anti-symmetric tensors of the
second bank in four dimensions". I tried to set up a story involving Jewish
industrialists who were elected to public office, and who owned farms, being
attacked by a bunch of jew-hating males from a local choir, who also happened
to work for the a small local bank, who had their farms surrounded and did
coordinated attacks from North, South, East and West. The punch line was to be
something "elected magnate's fields were defiled by anti-semitic tenors from
the Second Bank in four directions". But I never could come up with a story
that would end with that, and would bring to mind the corresponding physics so
as to make that a groan-worth pun.

------
d99kris
Below is my favorite math joke (copied it from
<http://www.onlinemathlearning.com/math-jokes-calculus.html> as I didn't
remember the exact wording). It's a bit long for a T-shirt, but a simple comic
strip version could be made.

\--

A constant function and e^x are walking on Broadway. Then suddenly the
constant function sees a differential operator approaching and runs away. So
e^x follows him and asks why the hurry. "Well, you see, there's this
differential operator coming this way, and when we meet, he'll differentiate
me and nothing will be left of me...!" "Ah," says ex, "he won't bother ME, I'm
e to the x!" and he walks on. Of course he meets the differential operator
after a short distance.

e^x: "Hi, I'm e^x"

diff.op.: "Hi, I'm d/dy"

~~~
jrockway
I think I might have to add "Hi, I'm d/dy" to my mail signature collection. So
random.

------
troymc
xkcd comics are already licensed under a Creative Commons Attribution-
Noncommercial 2.5 license. That's probably all you need for a math team
t-shirt.

~~~
whackedspinach
I saw that, but in the end some of the images are only about 700x400 px. At
200 ppi (which is what t shirts should be printed at, I guess), that just
isn't a high enough resolution. And I'm not sure If I really want to make it
larger since it will not look all that good.

~~~
troymc
You could load an xkcd comic into Inkscape or another vector graphics editor
and trace it out by hand. It wouldn't take that long, and the end result would
be a vector graphic that you could render to whatever size or resolution you
need. (Creating a derivative work like this is allowed by the license.)

------
templaedhel
Not short enough for a shirt probably, but still good:

Three mathematicians and three accountants are traveling by train to a
conference. At the station, the three accountants each buy tickets and watch
as the three mathematicians buy only a single ticket.

"How are three people going to travel on only one ticket?" asks an accountant.
"Watch and you'll see," answers an mathematician. They all board the train.
The accountants take their respective seats but all three mathematicians cram
into a restroom and close the door behind them.

Shortly after the train has departed, the conductor comes around collecting
tickets. He knocks on the restroom door and says, "Ticket, please." The door
opens just a crack and a single arm emerges with a ticket in hand. The
conductor takes it and moves on.

The accountants saw this and agreed it was quite a clever idea. So after the
conference, the accountants decide to copy the mathematicians on the return
trip and save some money (being clever with money, and all). When they get to
the station they buy a single ticket for the return trip.

To their astonishment, the mathematicians don't buy a ticket at all. "How are
you going to travel without a ticket?" asked one perplexed accountant.

"Watch and you'll see," answered an mathematician. When they board the train
the three accountants cram into a restroom and the three mathematicians cram
into another one nearby. The train departs.

Shortly afterward, one of the mathematicians leaves his restroom and walks
over to the restroom where the accountants are hiding. He knocks on the door
and says, "Ticket, please."

~~~
GrandMasterBirt
my wife laughed. This one passes.

------
patio11
Math team: like being star quarterback, except you have to wait ten years
before you can order the football team around.

------
cperciva
If you do it in groups, you'd better be discrete.

(Related: Analysts do it continuously, and almost everywhere.)

~~~
patio11
Materials scientists do it with latex.

Biochemists do it with animals.

When civil engineers do it, the earth moves.

Software engineers do it all night long.

~~~
mahmud
mathematicians do it in theory

(pretty old one)

~~~
mirkules
Does that mean physicists do it in practice?

------
cheald
Q: Did you hear about the constipated mathematician?

A: He worked it out with a pencil.

This one _always_ gets someone to cringe. I love it.

Alternately:

Q: How many mathematicians does it take to change a lightbulb?

A: One. The mathematician hands the lightbulb to two blondes, thereby reducing
the problem to a previously-told joke.

------
marcuswestin
There are two hard problems in computer science. Naming, cache invalidation,
and off-by-one errors.

~~~
nayanshah
Make that 10 hard problems.

Similar to - There are 10 kinds on people. Those who understand binary and
those who don't.

~~~
rcfox
Every base is base 10.

<http://cowbirdsinlove.com/43>

~~~
gurraman
I found this one particularly amusing :)

~~~
brk
It took me a while to notice the aliens hands...

------
j_baker
A physicist, a biologist, and a mathematician see two people walk into an
empty building. Five minutes later, 4 people walk out.

The physicist says "Obviously our initial observation was wrong."

The biologist says "They must have multiplied while they were in the
building!"

The mathematician says "However you look at it, if two more people walk into
that building it will be empty again."

------
pillmuncher
An engineer, a physicist and a mathematician want to catch a lion. The
engineer goes to Africa, builds a cage and traps the lion in it. The physicist
builds a fence around Africa and pronounces: "I've trapped the lion". The
mathematician builds a cage, climbs inside and pronounces: "I am outside".

------
waterhouse
In the fall of 2009, Mr. Apollinax discovered a method of simplifying
mathematical expressions with profound, wide-ranging consequences. Mr.
Apollinax has given it the name "indiscriminate cancellation". We see its
power and reliability here:

    
    
      16/64 = 1/4 ;Cancel the 6
      19/95 = 1/5 ;Cancel the 9
      26/65 = 2/5 ;Cancel the 6
      49/98 = 4/8 ;Cancel the 9
    

Using his new tool, Mr. Apollinax quickly discovered and prove several
surprising theorems, including the following:

    
    
      sin x / n = six ;Cancel the n
    

But the most celebrated application of this method of Mr. Apollinax is his
amazing discovery of a deep, unexpected connection between the theories of
complex numbers and trigonometry and the preparation of Mexican cuisine:

    
    
      sin / cos = tan ;definition of tangent
      i / co = ta ;cancel n and s
      i = taco ;multiply both sides by co
    

[Martin Gardner wrote a couple of April 1st columns about Mr. Apollinax. Worth
checking out. Also, it's kind of a cool computer science problem to find
number pairs like 16/64. I'll mention that if we generalize it to "abcd...x /
bcd...xy = a/y", then there are seven nontrivial (where a,b,c,etc. aren't all
the same digit) 3-digit pairs, including 484/847.]

------
sinc
Math problems? Call 1-800-[(10x)(13i)2]-[sin(xy)/2.362x].

(From <http://www.math.ualberta.ca/~runde/jokes.html>)

~~~
anigbrowl
This is by far the best t-shirt candidate.

------
ronnoch
Math Overflow had a joke thread a while back:
[http://mathoverflow.net/questions/1083/do-good-math-jokes-
ex...](http://mathoverflow.net/questions/1083/do-good-math-jokes-exist)

------
abeppu
An evil dictator locks up all the academics in his country in a time of war.
As the war worsens the army platoon left guarding the detention facility is
called away to the front, and leaves the academics unattended in their cells
bottled water, canned food and no can openers. When the war is over and the
dictatorship is collapsed, the detention facility is opened up. It's found
that most of the humanities and social scientists have survived, having opened
their cans by throwing them randomly at the walls until the cans broke open.
The physicists had figured out the optimum angle at which to throw the can in
order to reliably open it. Several mathematicians have suffered severe
malnutrition, having successfully proven that "there exists a unique optimal
throwing angle theta ..." The cell of a topologist was found empty, though a
muffled screaming could be heard from one of his cans. A can opener is
fetched, and the topologist is removed, covered in food, mumbling about an
error in sign.

------
PeterWhittaker
Years ago, three friends from Poland decided to visit relatives in the US they
had not seen for decades. Since this was a once-in-a-lifetime trip, they did
in grand style, on the Concorde.

Of course, there was trouble on the flight and of course the flight attendants
asked if any of the passengers had experience with aircraft, and of course one
of our friends did. He was taken to the cockpit to save the day, wherein he
looked at the myriad dials and gauges and controls and turned to his friend
and said... ...wait for it...

"I am but a simple Pole in a complex plane."

------
iuguy
One for HN:

Q: Why did the two vectors start an internet-based company?

A: Because they thought they had a good dot product.

One for a t-shirt (stolen off the Internet):

Math problems? Call 1-800-[(10x)(13i)^2]-[sin(xy)/2.362x].

~~~
twymer
In terms of t-shirt type statements, I think this is the best I've read on
here.

------
panic
There's always the classic, 'Snakes ⊂ ℝ²'.

~~~
mcrittenden
Can someone explain this one?

~~~
waterhouse
ℝ² is the Cartesian plane; it is a reference to the movie "Snakes On A Plane".

------
rcfox
Q: What do you get when you cross a mosquito with a mountain climber?

A: You can't cross a vector with a scalar!

~~~
shadowpwner
I'm sorry, how is a mosquito a vector?

~~~
jsundram
mosquitos are vectors for disease
(<http://en.wikipedia.org/wiki/Vector_(biology)>)

------
TamDenholm
Why did the chicken cross the Möbius strip?

To get to the same side.

~~~
troymc
This joke might be funnier if the answer is:

To get to the other side.

(The mathematicians will know that the chicken's quest will fail. Then they'll
feel sorry for the chicken...)

~~~
dcbell
But the non-mathematicians will JUST give you a weird look, rather than
laughing and then giving you a weird look.

~~~
troymc
I don't know. A cliche can seem funny if you add a little twist, even if the
twist is incomprehensible.

------
sammcd
Surprised this isn't already here, pretty popular at my college:

I wish I was your derivative, so I could lie tangent to your curves.

~~~
sliverstorm
And the companion bio-joke:

I wish I was mRNA polymerase, so I could unzip your genes.

~~~
joshzayin
Helicase is what unzips the genes, not RNA polymerase. RNA polymerase allows
transcription (or creation of an mRNA molecule complementary to the given
gene) to take place.

------
edanm
Not sure you can copy it, but I've always wanted this shirt (not sure why, but
I found it hilarious):

[http://www.thinkgeek.com/tshirts-
apparel/unisex/generic/60f5...](http://www.thinkgeek.com/tshirts-
apparel/unisex/generic/60f5/)

It reads:

2 + 2 = 5

(For extremely large values of 2)

------
toufique
My all time favorite is "Find x":
<http://www.ximnet.com.my/thelab/images/upload/findX.jpg>

"Be Rational" and "Get Real" is pretty good too:
[http://media.photobucket.com/image/rational/CocaC0la99/be-
ra...](http://media.photobucket.com/image/rational/CocaC0la99/be-rational-get-
real.png)

------
Towle_
"Leibnitz > Newton" could provoke a fist fight. This would be hilarious to
see.

edit: Better than xkcd, depending on your sense of humor (i.e., whether you
have one) is smbc-comics.com. Dunno how he licenses his stuff though.

------
Typhon
An old one :

Why do mathematician mistake Halloween for Christmas ?

Because to them, 31oct = 25dec

------
Sukotto
Front: (a^n) + (b^n) = (c^n) true only when n <= 2 if a,b,c are positive
integers.

Back: I have discovered a truly marvelous proof but this shirt is too too
narrow to contain it

~~~
tiki12revolt
Or, why I spent ten years in an attic on a silly proof.

It was something like ten years Andrew Wiles spent on it, wasn't it?

------
pom
Here's one but it's in French.

"Qui se cache derrière le nombre 1.09861228866811... ?" "Hélène de Troie. (ln
3)"

------
nkassis
There's always the old donut and coffee mug being topologically equivalent.

Or the integral of e^X (write it down)

Or Pi telling i to be real and i telling Pi to be rational.

Or your mom so ugly I had to use the Fourier transform to solve her (just made
that one up, probably doesn't make any sense ;p)

~~~
nayanshah
+1 for Pi telling i to be real and i telling Pi to be rational

~~~
TeMPOraL
<http://roflcopter.pl/math-jokes.jpg>

------
thechangelog
What's the square root of 69? Eight something.

------
nagrom
Good math jokes split into two groups: either they're funny, or they make you
feel clever for understanding them, I think. The latter are more fun.

Simple Level:

What's special about plants in the maths common room?

They have square roots.

More Educated:

Why can't you plant wheat in the integers mod 6?

Because 6 isn't prime!

------
alok-g
"Life is complex is because it has both real and imaginary components."

Cannot recall the source.

------
corin_
I love the people in this thread giving jokes that are aimed at five year
olds, rather than a math team who's previous joke was "don't drive and
derive".

------
kaiser_pelagic
Q: what did the zero say to the eight? A: nice belt!

~~~
hrrld
An all time favorite of mine! (:

------
alok-g
A friend of mine once claimed that a specific celebrity couple had their ages
as 88 years and 44 years respectively. All others said that they knew the age
difference was big for this couple, but it couldn't be that big! Some more
probing and my friend blurted "I remember exactly that when they got married,
they were 44 and 22 respectively".

------
alok-g
Question:Whatz a PJ ? Answer: Obviously "a poor joke" Question: Whatz a (P +
iJ)? Answer: "complex poor joke" But why don't people laugh on a "complex poor
joke"? Bcoz the joke part of it is imaginary.

<http://www.akhilesh.in/life/fun/jokes/pj0061AComplexPJ.php>

------
hsuresh
<http://en.wikipedia.org/wiki/Math_jokes>

------
nayanshah
Love this one : <http://spikedmath.com/325.html>

~~~
lotharbot
I'd recommend digging through the spiked math "best of" list and looking for
something that suits the math team's fancy.

(x,why?) can also be quite entertaining.

------
RiderOfGiraffes
There are 10 kinds of methematicians, those that count in ternary and those
that don't.

(Not many people, even mathematicians and computer scientists, get that one. I
think it's better than the usual crap binary non-joke, and wish I could
remember where I heard it)

------
ljf
There are 10 kinds of people in the world, those who understand binary and
those who don't.

------
gnubardt
whats a chefs favorite triangle? isauceles

how did the abelian group get to work? it commuted

why do addition and the integers carpool? because theyre a commutative group

------
DeusExMachina
At a party, all mathematical functions are having fun, except the exponential,
which is standing lonely in one corner. Another function approaches it and
says: why don't you integrate? And it: oh, because it's the same...

------
Evgeny
Not sure if that can fit on the t-shirt, but here are couple of ideas

[http://farm3.static.flickr.com/2174/2268237733_cda4a1dbb3.jp...](http://farm3.static.flickr.com/2174/2268237733_cda4a1dbb3.jpg)

[http://geektech.geektech.netdna-cdn.com/wp-
content/uploads/2...](http://geektech.geektech.netdna-cdn.com/wp-
content/uploads/2010/06/719a20f3a2e4.jpg)

(these are 'captchas' that require you to solve a problem)

Also, liked these (unrelated to maths):

[http://geektechnica.com/2010/06/10-craziest-captchas-out-
the...](http://geektechnica.com/2010/06/10-craziest-captchas-out-there/)

------
dwwoelfel
What is the par value of a zero-coupon bond with no maturity?

Pee dollars!

Did you see the SNL segment on options? It was put-call parody!

Complex analysis: it's as easy as pulling out an i.

Analysis, something, something. Balls! (I haven't quite finished that one).

------
kyro
What do you get when you cross an elephant and a banana?

(Elephant)(banana)sin(theta)

------
crasshopper
Maybe you could fit just the punchline on a T-shirt:

A sociologist, a physicist, and a mathematician are given 100 ft of fence and
asked to enclose the greatest area.

-The sociologist makes a square. -The physicist makes a circle and says he can PROVE it's the best answer. Take that, mathematician! -The mathematician knocks off all but a few fence-links, wraps the fence around himself, and says "Define the outside of the fence to be the ground which contains me..."

(Say the punchline in a smarmy, nasal voice.)

------
hansman
Physicist, pastor and mathematician on the top of a skyscraper. They are asked
to jump precisely into the swimming pool on the ground. Phsycist calculates
wind, distance, perspective, jumps and lands in the pool. Pastor meditates,
prays, focuses, jumps and lands in the pool. Mathematician calculates a
beautiful parabel, jumps and goes straight up to the sky. What happend? Oh
well, he made a sign flaw :)

------
drblast
An engineer and a mathematician went out for a drink. On the other side of the
room, they spotted a gorgeous woman.

"I wish I could work up the courage to talk to her," said the shy
mathematician.

"No problem," said the engineer. "Just walk halfway over to her, take a sip of
beer, then walk halfway again, and do that over and over until you're next to
her.

"But then I'll NEVER get there," said the mathematician.

------
sz
<http://www.wolframalpha.com/input/?i=Tell+me+a+joke>.

------
sahillavingia
A sahillavingia original:

Q: What did the difficult cartesian-coordinate system tell his problem-solver
when he wanted to visit Antartica?

A: You should go polar!

------
eam
_i_ 8 √-1 Πs. (I ate imaginary pies?) You might have to play around with it,
but I hope it's a good start. :)

------
rcthompson
If you want to incorporate ideas from xkcd without using any of the published
comics, you could come up with your own nerd snipe and put it on the front of
your shirt. Then put something on the back like "You've been nerd-sniped!"

Make sure to hang out near busy streets and train tracks when you wear it.

------
plaes
Don't know whether this fits as a joke, but:

    
    
        exp(I*pi) + 1 = 0

~~~
spectre
Thats not a joke its an import mathematical identity.

<http://en.wikipedia.org/wiki/Euler%27s_identity>

------
alok-g
"Spherical bastard: Someone who's a bastards from every viewpoint"

<http://scienceworld.wolfram.com/biography/Zwicky.html>

------
tnai
Not sure where I heard this ...

Biology is really Chemistry. Chemistry is really Physics. Physics is really
Maths. and Maths is really hard.

------
stretchwithme
Its not a joke but a series of punny things crammed into a catchy song:

    
    
      http://www.youtube.com/watch?v=BipvGD-LCjU

------
alok-g
<http://www.math.ualberta.ca/~runde/jokes.html>

------
Roedou
Q: What the integral of (1/cabin)dCabin?

A: Beach Hut

(Log Cabin + C)

[Maybe just the formula would fit on a T Shirt, and you get to explain it to
people who ask?]

~~~
jpwagner
Q: Integral dCabin/Cabin?

A: natural log cabin

------
anigbrowl
Eat the pie, I; my new swan is nothing.

------
ookblah
friend had a shirt that said

"be there or c squared minus a squared"

lol

------
durbin
I've always wanted a t shirt that said "I love LAMP" with a picture of a
computer on it.

------
DavidSJ
A mathematician got something stuck up his ass. He worked it out with a
pencil.

------
drallison
assume: x = y then: x _x = x_ y and then: x _x - y_ y = x _y - y_ y factor:
(x+y) _(x-y) = y_ (x-y) cancel: x+y = y replace: x + x = x simplify: 2 * x = x
therefore: 2 = 1 QED

------
corin_
According to statistics, a normal person has one breast and one testicle...

~~~
klodolph
I object! The average person has less than one breast and less than one
testicle.

~~~
twymer
I object again! Statistics say there are slightly less men than women in the
states. Therefore, the average person has more than one breast and less than
one testicle.

[http://en.wikipedia.org/wiki/Demographics_of_the_United_Stat...](http://en.wikipedia.org/wiki/Demographics_of_the_United_States)

~~~
cheald
I object yet again! Mastectomies surely offset the breast:testicle ratio to a
statistically-significantly degree!

------
danielson
Q) What did the Zen Buddhist say to the hot dog vendor?

~~~
danielson
A) Make me One with everything.

------
alok-g
Not really a joke, but possibly good for a t-shirt:

"sec(C)"

~~~
kaokun
What about:

"I'm too 1/cos(C) for my shirt"

------
bosky101
here's one from the last decade.

Q. what did the math teacher say when she saw tennis star monica seles?

A. isosceles

------
kingsidharth
Why was 6 afraid of 7?

Because 7 8 9!

(7 ate 9)

~~~
DavidSJ
I think you mean (ate 7 9). Don't feel bad, infix notation can creep up even
on experienced Lisp programmers.

~~~
kingsidharth
Those brackets were not for Lisp! God! They are also used for English.

------
golwengaud
Real analysis takes balls.

------
kleiba
Let epsilon < 0

------
brettjamin
Let ε < 0.

------
drallison
assume: x = y then: x^2 = y^2

------
zackattack

       Math Club
    

then put a picture of a hot chick, and some MDMA

then _Transcendental Numbers_

------
tkahn6
There are three types of mathematicians. Those who can add and those who
can't.

------
shareme
1i + 1i = 2i

Cannot have Magic without the i

