Bad Math Jokes

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etotheipi said:
$$2x = \frac{d}{dx}(x^2) = \frac{d}{dx} (\underbrace{x + \dots + x}_{x \, \mathrm{times}}) = \underbrace{1 + \dots + 1}_{x \, \mathrm{times}} = x$$Hence, ##2=1##. :wink:
Hah, that made me chuckle. That's a cute attempt, though :D A lot of people might sleep on the ##x## times business.
 
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etotheipi said:
"You see officer, whilst it's true that I was going 80 mph on that dual carriageway, Dr Greg proved that in fact 80 = 70 and so, mathematically, this fine is unjustified..."
Judge: Excellent point, Mr Pi. So you will find it no greater hardship that I have doubled the fine.
 
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etotheipi said:
$$2x = \frac{d}{dx}(x^2) = \frac{d}{dx} (\underbrace{x + \dots + x}_{x \, \mathrm{times}}) = \underbrace{1 + \dots + 1}_{x \, \mathrm{times}} = x$$Hence, ##2=1##. :wink:
Corollary: All numbers are equal.

Proof: $$\begin{align*}
2 &= 1 \\
\implies 2(b-a) &= b-a \\
\implies b-a &= 0 \\
\implies a &= b \\
\end{align*}$$
 
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If all numbers are equal then the Riemann hypothesis is both true and false.

* Every point is a root as every function value is equal to zero.
* There is no root outside the critical strip as every point of the domain is equal to the critical strip.

This might sound like a contradiction, but it just extends the original point by showing that also true=false.
 
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DrGreg said:
All numbers are equal! Let ##a## and ##b## be any two numbers and define$$
c = a + b.
$$Multiply both sides by ##a-b##:$$
(a - b)c = (a - b)(a+b).
$$Expand:$$
ac - bc = a^2 - b^2.
$$Rearrange:$$
b^2 - bc = a^2 - ac.
$$Add ##ab## to both sides:$$
ab + b^2 - bc = a^2 + ab - ac.
$$Factorise:$$
(a+b-c)b = (a+b-c)a.
$$Cancel:$$
b=a
$$QED.

One cannot cancel a zero factor

since c=a+b => a+b-c=0
 
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1617435567922.png
 
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A passenger jet takes off from Warsaw. Suddenly both pilot and copilot suffer heart attacks. The stewardess panics and announces to the passengers, "Is there a doctor on board?" A man stands and says, "I know some first aid." She rushes him to the pilot's cabin where he discovers both pilot and copilot have died. She desperately cries, "You have to land the plane!" The man looks around and says, "I can't do that! I'm just a simple Pole on a complex plane."
 
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H9Ooy83.jpg
 
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I probably told it before, but it is a really bad one:

A professor held his lectures and there were only three students in the auditorium. To make it even worse, after fifteen minutes five of them stood up and left the room. "D...", thought the professor, "I hope there will be coming another two so I can leave as well."
 
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fresh_42 said:
I probably told it before, but it is a really bad one:

A professor held his lectures and there were only three students in the auditorium. To make it even worse, after fifteen minutes five of them stood up and left the room. "D...", thought the professor, "I hope there will be coming another two so I can leave as well."
There's a similar joke (don't try to analyse this too much, it's full of logical holes):

A biologist, a physicist and a mathematician are in a coffee shop watching another shop across the street. For a long time nothing happens, then two people enter the other shop and shortly after three people leave. They ask each other, how is it possible for two to enter and three to leave?

The biologist says it's an example of reproduction.

The physicist says it's experimental error.

The mathematician says, if another person enters the shop there'll be nobody in there.
 
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Imagine a joke involving a distance ##t## and a time ##r## !
Schwartzschild coordinates inside the event horizon.
 
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Guy is flying over the Grand Canyon sitting next to an accountant. Looks over to the accountant and says ‘that sure is impressive’.
Accountant says ‘yes, it’s one hundred million and three years old’
Guy says ‘hundred million and three? How do you know that?’
Accountant says ‘three years ago I was on this same flight sitting next to a geologist and he told me’
 
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BWV said:
Guy is flying over the Grand Canyon sitting next to an accountant. Looks over to the accountant and says ‘that sure is impressive’.
Accountant says ‘yes, it’s one hundred and three million years old’
Guy says ‘hundred and three million? How do you know that’
Accountant says ‘three years ago I was on this same flight sitting next to a geologist and he told me’
Nice joke, but you really meant to say "one hundred million and three", not "one hundred and three million". :smile:
 
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