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Berry Paradox
Ngeliat dari http://en.wikipedia.org/wiki/Berry_paradox




Consider the following expression:
----The smallest positive integer not definable in under eleven words.

The question is:
----Is there any?

Since there are finitely many words, there are finitely many phrases of under eleven words, and hence finitely many positive integers that are defined by phrases of under eleven words. Since there are infinitely many positive integers, this means that there are positive integers that cannot be defined by phrases of under eleven words - that is, positive integers satisfying the property "not definable in under eleven words".

By the well ordering principle, if there are positive integers that satisfy a given property, then there is a smallest positive integer that satisfies that property; therefore, there is a smallest positive integer satisfying the property "not definable in under eleven words". This is the integer to which the above expression refers; that is, this integer is defined by the above expression.

But note that the above expression is only ten words long; so, this integer is defined by an expression that is under eleven words long; so it is definable in under eleven words, and is not the smallest positive integer not definable in under eleven words, and is not defined by this expression.

This is a paradox: there must be an integer defined by this expression, but since the expression is self-contradictory (any integer it defines is, clearly, definable in under eleven words), there cannot be any integer defined by it.





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Math Jokes
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smiley --> menandakan level kelucuan! (menurut gw...)




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Q: How does one insult a mathematician?
A: You say: "Your brain is smaller than any image>0!"


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


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Theorem. Every positive integer is interesting.

Proof. Assume towards a contradiction that there is an uninteresting positive integer. Then there must be a smallest uninteresting positive integer. But being the smallest uninteresting positive integer is interesting by itself. Contradiction!


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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.


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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 e^x..."

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 e^x..."
"Too bad... I'm d/dy."


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Did you know that 5 out of every 4 people have a problem with fractions?


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Engineer, physicist and mathematician are asked to find the value of 2+2.
Engineer (after 3 minutes, with a slide rule): "The answer is precisely 3.9974."
Physicist (after 6 hours of experiments): "The value is approximately 4.002, with an error of plus-or-minus 0.005."
Mathematician (after a week of calculation): "Well, I haven't found an answer yet but I can prove that an answer exists."


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Two mathematicians went out to lunch. Over lunch, one complained that most people don't understand even basic math. The other took a more optimistic view. A short time later, while the pessimist was in the bathroom, the other called the waitress over. "I am going to call you over in a few minutes," he explained, "and I am going to ask you a question. I want you to answer X^3/3. OK?"....When the pessimist came back, he called the waitress over. "Look, I'll prove people understand math better than you think. OK, young lady, what is the integral of X^2?"... "X^3/3" she slowly repeated and walked away. Then she turned around and said,
"Plus a constant."