Q: What does the little mermaid wear?
A: An algae-bra.
A mathematical biologist spends his vacation hiking in the Scottish highlands. One day, he encounters a shepherd with a large herd of sheep. One of these cuddly, woolly animals would make a great pet, he thinks...
"How much for one of your sheep?" he asks the shepherd.
"They aren't for sale", the shepherd replies.
The math biologist ponders for a moment and then says: "I will give you the precise number of sheep in your herd without counting. If I'm right, don't you think that I deserve one of them as a reward?"
The shepherd nods.
The math biologist says: "387".
The shepherd is silent for a while and then says: "You're right. I hate to loose any of my sheep, but I promised: One of them is yours. Have your pick!"
The math biologist grabs one of the animals, puts it on his shoulders, and is about to march on, when the shepherd says: "Wait! I will tell you what your profession is, and if I'm right I'll get the animal back."
"That's fair enough."
"You must be a mathematical biologist."
The man is stunned. "You're right. But how could you know?"
"That's easy: You gave me the precise number of sheep without counting - and then you picked my dog..."
A logician at Safeway.
"Paper or plastic?"
"Not 'not paper and not plastic'!"
"Isn't statistics wonderful?"
"How so?"
"Well, according to statistics, there are 42 million alligator eggs laid every year. Of those, only about half get hatched. Of those that hatch, three fourths of them get eaten by predators in the first 36 days. And of the rest, only 5 percent get to be a year old for one reason or another. Isn't statistics wonderful?"
"What's so wonderful about all that?"
"If it weren't for statistics, we'd be up to our asses in alligators!"
One day, Jesus said to his disciples: "The Kingdom of Heaven is like 3x squared plus 8x minus 9."
A man who had just joined the disciples looked very confused and asked Peter: "What, on Earth, does he mean by that?"
Peter replied: "Don't worry - it's just another one of his parabolas."
Q: What is the fundamental principle of engineering mathematics?
A: Every function has a Taylor series which converges to the function and breaks off after the linear term.
"Wasn't yesterday your and your wife's first wedding anniversary? What is it like having being married to a mathematician for a whole year?"
"She just filed for divorce..."
"I don't believe it! Did you forget about your wedding day?"
"No. Actually, on my way back home from work, I stopped at a flower store and bought a bouquet of red roses for my wife. When I came home, I gave her the roses and said: `I love you.'"
"So, what happened?!"
"Well, she took the roses, slapped them around my face, kicked me in the groin, and threw me out of our apartment..."
"What a bitch!"
"No, no... it's all my fault... I should have said: `I love you and only you.'."
A pure and an applied mathematician are asked to calculate 2 * 2.
The applied mathematician's solution: We have
2 * 2 = 2 *1/(1-1/2).
The second factor on the right hand side has a geometric series expansion
1/(1-1/2) = 1 + 1/2 +1/4 + 1/8 + ....
Cutting off the series after the second term yields the approximate solution
2 * 2 = 2 *(1 +1/2) = 3.
The pure mathematician's solution: We have
2 * 2 = (-2) *1/(1-3/2).
The second factor on the right hand side has a geometric series expansion
1/(1-3/2) = 1 + 3/2 +9/4 + 27/8 + ...,
which diverges. Hence, the solution to 2 * 2 does not exist.
A physics professor has been conducting experiments and has worked out a set of equations which seem to explain his data. Nevertheless, he is unsure if his equations are really correct and therefore asks a colleague from the math department to check them.
A week later, the math professor calls him: "I'm sorry, but your equations are complete nonsense."
The physics professor is, of course, disappointed. Strangely, however, his incorrect equations turn out to be surprisingly accurate in predicting the results of further experiments. So, he asks the mathematician if he was sure about the equations being completely wrong.
"Well", the mathematician replies, "they are not actually complete nonsense. But the only case in which they are true is the trivial one where the field is Archimedean..."
"The number you have dialed is imaginary. Please, rotate your phone by 90 degrees and try again..."
Q: Do you already know the latest stats joke?
A: Probably...
Q: Why do mathematicians often confuse Christmas and Halloween?
A: Because Oct 31 = Dec 25.
A mathematician gives a talk intended for a general audience. The talk is announced in the local newspaper, but he expects few people to show up because nobody who is not a mathematician will be able to make any sense of the title: Convex sets and inequalities.
To his surprise, the auditorium is crammed when his talk begins. After he has finished, someone in the audience raises his hand.
"But you said nothing about the actual topic of your talk!"
"What topic to you mean?"
"Well, the one that was announced in the paper: Convicts, sex, and inequality."
George W. Bush visits Algeria. As part of his program, he delivers a speech to the Algerian people: "You know, I regret that I have to give this speech in English. I would very much prefer to talk to you in your own language. But unfortunately, I was never good at algebra..."
At the end of his course on mathematical methods in optimization, the professor sternly looks at his students and says: "There is one final piece of advice I'm going to give you now: Whatever you have learned in my course - never ever try to apply it to your personal lives!"
"Why?" the students ask.
"Well, some years ago, I observed my wife preparing breakfast, and I noticed that she wasted a lot of time walking back and forth in the kitchen. So, I went to work, optimized the whole procedure, and told my wife about it."
"And what happened?!"
"Before I applied my expert knowledge, my wife needed about half an hour to prepare breakfast for the two of us. And now, it takes me less than fifteen minutes..."
A French mathematician's pick up line: "Voulez vous Cauchy avec moi?"
"My life is all arithmetic", the young businesswoman explains. "I try to add to my income, subtract from my weight, divide my time, and avoid multiplying..."
A graduate student of mathematics who used to come to the university on foot every day arrives one day on a fancy new bicycle.
"Where did you get the bike from?" his friends want to know.
"It's a `thank you' present", he explains, "from that freshman girl I've been tutoring. But the story is kind of weird..."
"Tell us!"
"Well", he starts, "yesterday she called me on the phone and told me that she had passed her math final and that she wanted to drop by to thank me in person. As usual, she arrived at my place riding her bicycle. But when I had let her in, she suddenly took all her clothes off, lay down on my bed, smiled at me, and said: `You can get from me whatever you desire!'"
One of his friends remarks: "You made a really smart choice when you took the bicycle."
"Yeah", another friend adds, "just imagine how silly you would have looked in a girl's clothes - and they wouldn't have fit you anyway!"
Q: What is normed, complete, and yellow?
A: A Bananach space...
A father who is very much concerned about his son's bad grades in math decides to register him at a catholic school. After his first term there, the son brings home his report card: He's getting "A"s in math.
The father is, of course, pleased, but wants to know: "Why are your math grades suddenly so good?"
"You know", the son explains, "when I walked into the classroom the first day, and I saw that guy on the wall nailed to a plus sign, I knew one thing: This place means business!"
At a conference, a mathematician proves a theorem.
Someone in the audience interrupts him: "That proof must be wrong - I have a counterexample to your theorem."
The speaker replies: "I don't care - I have another proof for it."
A mathematician has been invited to speak at a conference. His talk is announced as
Proof of the Riemann hypothesis.
When the conference actually takes place, he speaks about something completely different.
After his talk, a colleague asks him: "Did you find an error in your proof?"
He replies: "No - I never had one."
"But why did you make this announcement?"
"That's my standard precaution - in case I die on my way to the conference..."
The mother of already three is pregnant with her fourth child.
One evening, the eldest daughter says to her dad: "Do you know, daddy, what I've found out?"
"No."
"The new baby will be Chinese!"
"What?!"
"Yes. I've read in the paper that statistics shows that every fourth child born nowadays is Chinese..."
A math student and a computer science student are jogging together in a park when they hear a voice: "Please, help me!"
They stop and look. The voice belongs to a frog sitting in the grass.
"Please, help me!" the frog repeats. "I'm not really a frog: I'm an enchanted, beautiful princess. Kiss me, and the spell will be broken - and I will be yours forever..."
The CS student picks up the frog and examines it carefully from all sides - making not even an attempt to kiss it.
"You don't have to marry me", the frog continues frantically, "if you're afraid of the commitment. I'll do whatever you wish me to do if you just kiss me..."
The frog's voice is silenced, when the CS student puts the animal into the right pocket of his pants.
"But why don't you kiss her?!" the math student asks.
"You know", the CS student replies, "I simply don't have time for a girlfriend - but a frog that talks makes a really cool pet..."
Psychologists subject an engineer, a physicist, and a mathematician - a topologist, by the way - to an experiment: Each of them is locked in a room for a day - hungry, with a can of food, but without an opener; all they have is pencil and paper.
At the end of the day, the psychologists open the engineer's room first. Pencil and paper are unused, but the walls of the room are covered with dents. The engineer is sitting on the floor and eating from the open can: He threw it against the walls until it cracked open.
The physicist is next. The paper is covered with formulas, there is one dent in the wall, and the physicist is eating, too: He calculated how exactly to throw the can against the wall, so that it would crack open.
When the psychologists open the mathematician's room, the paper is also full of formulas, the can is still closed, and the mathematician has disappeared. But there are strange noises coming from inside the can...
Someone gets an opener and opens the can. The mathematician crawls out. "Damn! I got a sign wrong..."
A physicist, a statistician, and a (pure) mathematician go to the races and place bets on horses.
The physicist's horse comes in last. "I don't understand it. I have determined each horse's strength through a series of careful measurements."
The statistician's horse does a little bit better, but still fails miserably. "How is this possible? I have statistically evaluated the results of all races for the past month."
They both look at the mathematician whose horse came in first. "How did you do it?"
"Well", he explains. "First, I assumed that all horses were identical and spherical..."
A physicist, a mathematician and a computer scientist discuss what is better: a wife or a girlfriend.
The physicist: "A girlfriend. You still have freedom to experiment."
The mathematician: "A wife. You have security."
The computer scientist: "Both. When I'm not with my wife, she thinks I'm with my girlfriend. With my girlfriend it's vice versa. And I can be with my computer without anyone disturbing me..."
Q: What is a topologist?
A: A person who cannot tell a doughnut from a coffee mug.
"What happened to your girlfriend, that really cute math student?"
"She no longer is my girlfriend. I caught her cheating on me."
"I don't believe that she cheated on you!"
"Well, a couple of nights ago I called her on the phone, and she told me that she was in bed wrestling with three unknowns..."
A group of mathematicians and a group of engineers are traveling together by train to attend a conference on mathematical methods in engineering. Each engineer has a ticket whereas only one of the mathematicians has one. Of course, the engineers laugh at the unworldly mathematicians and look forward to the moment the conductor shows up.
Suddenly one of the mathematicians shouts: "Conductor coming!"
All the mathematicians disappear into one washroom.
The conductor checks the ticket of each engineer and then knocks at the washroom door: "Your ticket, please."
The mathematicians stick the one ticket they have under the door, the conductor checks it and leaves. A few minutes later, when it is safe, the mathematicians come out of the washroom. The engineers are impressed.
When the conference has come to an end, the engineers decide that they are at least as smart as the mathematicians and also buy just one ticket for the whole group. This time the mathematicians have no ticket at all...
Again one of the mathematicians shouts: "Conductor coming!".
All the engineers rush off to one washroom. One of the mathematicians goes to that washroom, knocks at the door, and says: "Your ticket, please..."
In the old days of the cold war, when it was very hard for Westerners to visit the Soviet Union, a British mathematician travels to Moscow to speak in the seminar of a famous Russian professor.
He starts his talk writing a theorem on the board. When he wants to prove it, the professor interrupts him: "This theorem is clear!"
The speaker is, of course, annoyed, but manages to conceal it. He continues his talk with a second theorem, but, again, when he wants to start with the proof, he is interrupted by his host: "This theorem is also clear!"
With a stern face, he writes a third theorem on the board and asks: "Is this theorem clear, too?!"
His host nods.
The visitor grins and says: "This theorem - is false..."
Some engineers are trying to measure the height of a flag pole. They only have a measuring tape and are quite frustrated trying to keep the tape along the pole: It falls down all the time.
A mathematician comes along and asks what they are doing. They explain it to him.
"Well, that's easy..."
He pulls the pole out of the ground, lays it down, and measures it easily.
After he has left, one of the engineers says: "That's so typical of these mathematicians! What we need is the height - and he gives us the length!"
A mathematician has spent years trying to prove the Riemann hypothesis - without success. Finally, he decides to sell his soul to the devil in exchange for a proof. The devil promises to deliver a proof within four weeks.
Four weeks pass, but nothing happens. Half a year later, the devil shows up again - in a rather gloomy mood.
"I'm sorry", he says. "I couldn't prove the Riemann hypothesis either. But" - and his face lightens up - "I think I found a really interesting lemma..."
Q: Was ist paradox an der Analysis?
A: Man faltet, um zu glätten...
The pun only works in German.
Q: How does a mathematician call his dog?
A: Cauchy - because it leaves a residue at every pole...
Two men are having a good time in a bar. Outside, there's a terrible thunderstorm. Finally, one of the men thinks that it's time to leave. Since he has drunk a lot, he decides to walk home.
"But aren't you afraid of being struck by lightning?" his friend asks.
"Not at all. Statistics shows that, in this part of the country, one person per year gets struck by lightning - and that one person died in the hospital three weeks ago."
After the phenomenal success of Viagra, Pfizer has come up with yet another pharmaceutical sensation: knowledge pills.
A student who is way behind in his English literature class, goes to the pharmacy, and asks the pharmacist if there are knowledge pills for English literature.
"Sure", the pharmacist replies.
The student buys one, swallows it, and hours later he knows everything there is to know about English literature. If it's that easy to acquire knowledge, he thinks, why waste hours wrecking your brains over boring textbooks? So, he gives up studying, and whenever an exam is near, he goes to the pharmacy and buys the right knowledge pill: biology, art history, world history - you name it.
When he has to take a math exam, he goes again to the pharmacy as asks for a knowledge pill for mathematics.
"Just wait a moment", the pharmacist says. He disappears in the back of his store and comes back with a pill of the size of a melon.
"But how am I supposed to swallow this?!" the student exclaims.
"Well, math has always been a little hard to swallow..."
In a class, a math professor claims that he can prove everything under the assumption that 1+1=1.
A student challenges him: "Then prove that you're the pope!"
He ponders for a moment and then replies: "I am one, and the pope is one. Therefore, the pope and I are one."
A mathematician, an engineer, and a computer scientist are vacationing together. They are riding in a car, enjoying the countryside, when suddenly the engine stops working.
The mathematician: "We came past a gas station a few minutes ago. Someone should go back and ask for help."
The engineer: "I should have a look at the engine. Perhaps, I can fix it."
The computer scientist: "Why don't we just open the doors, slam them shut, and see if everything works again?"
Let epsilon be less than zero...
Not really a joke, but rather a mathematician detection device: Tell it at a party, and those who laugh must be mathematicians.
Two math professors are sitting in a pub.
"Isn't it disgusting", the first one complains, "how little the general public knows about mathematics?"
"Well", his colleague replies, "you're perhaps a bit too pessimistic."
"I don't think so", the first one replies. "And anyhow, I have to go to the washroom now."
He goes off, and the other professor decides to use this opportunity to play a prank on his colleague. He makes a sign to the pretty, blonde waitress to come over.
"When my friend comes back, I'll wave you over to our table, and I'll ask you a question. I would like you to answer: x to the third over three. Can you do that?"
"Sure." The girl giggles and repeats several times: "x to the third over three, x to the third over three, x to the third over three..."
When the first professor comes back from the washroom, his colleague says: "I still think, you're way too pessimistic. I'm sure the waitress knows a lot more about mathematics than you imagine."
He makes her come over and asks her: "Can you tell us what the integral of x squared is?"
She replies: "x to the third over three."
The other professor's mouth drops wide open, and his colleague grins smugly when the waitress adds: "...plus C."
A mathematician, a physicist, and an engineer are asked to test the following hypothesis: All odd numbers greater than one are prime.
The mathematician: "Three is a prime, five is a prime, seven is a prime, but nine is not a prime. Therefore, the hypothesis is false."
The physicist: "Three is a prime, five is a prime, seven is a prime, nine is not a prime, eleven is a prime, and thirteen is a prime. Hence, five out of six experiments support the hypothesis. It must be true."
The engineer: "Three is a prime, five's a prime, seven's a prime, nine's a prime..."
In a dark, narrow alley, a function and a differential operator meet:
"Get out of my way - or I'll differentiate you till you're zero!"
"Try it - I'm ex..."
Same alley, same function, but a different operator:
"Get out of my way - or I'll differentiate you till you're zero!"
"Try it - I'm ex..."
"Too bad... I'm d/dy."
Back in the old days - when slide rules were still the most sophisticated computing equipment available to scientists and engineers...
Engineering students are taking a math final. Of course, slide rules are not allowed. And, of course, someone is cheating and has brought a slide rule to the exam. He is hiding it under his desk, but the student sitting to his left - who is stuck on a difficult calculation - has noticed it.
"Hey", he whispers. "Can you help me? What's three times six?"
His classmate reaches for his slide rule, and after a few seconds replies: "Nineteen."
"Are you sure?"
The other student reaches again for his slide rule, and after another few seconds replies: "You're right. It's closer to eighteen - eighteen point three, to be precise."
Two men are sitting in the basket of a balloon. For hours, they have been drifting through a thick layer of clouds, and they have lost orientation completely. Suddenly, the clouds part, and the two men see the top of a mountain with a man standing on it.
"Hey! Can you tell us where we are?!"
The man doesn't reply. The minutes pass as the balloon drifts past the mountain. When the balloon is about to be swallowed again by the clouds, the man on the mountain shouts: "You're in a balloon!"
"That must have been a mathematician."
"Why?"
"He thought long and thoroughly about what to say. What he eventually said was irrefutably correct. And it was of no use whatsoever..."