|
|
Mathematics
Home >
Mathematics
 |
Theorem: All numbers are equal.
Proof: Choose arbitrary a and b, and let t = a + b. Then
a + b = t
(a + b)(a - b) = t(a - b)
a^2 - b^2 = ta - tb
a^2 - ta = b^2 - tb
a^2 - ta + (t^2)/4 = b^2 - tb + (t^2)/4
(a - t/2)^2 = (b - t/2)^2
a - t/2 = b - t/2
a = b
So all numbers are the same, and math is pointless.
Hello, this is probably 438-9012, yes, the house of the famous statistician. I'm probably not at home, or not wanting to answer the phone, most probably the latter, according to my latest calculations. Supposing that the universe doesn't end in the next 30 seconds, the odds of which I'm still trying to calculate, you can leave your name, phone number, and message, and I'll probably phone you back. So far the probability of that is about 0.645. Have a nice day.
Prove that the crocodile is longer than it is wide.
Lemma 1. The crocodile is longer than it is green: Let's look at the crocodile. It is long on the top and on the bottom, but it is green only on the top. Therefore, the crocodile is longer than it is green.
Lemma 2. The crocodile is greener than it is wide: Let's look at the crocodile. It is green along its length and width, but it is wide only along its width. Therefore, the crocodile is greener than it is wide.
From Lemma 1 and Lemma 2 we conclude that the crocodile is longer than it is wide.
An engineer, a physicist, and a mathematician are trying to set up a fenced-in area for some sheep, but they have a limited amount of building material. The engineer gets up first and makes a square fence with the material, reasoning that it's a pretty good working solution. "No no," says the physicist, "there's a better way." He takes the fence and makes a circular pen, showing how it encompasses the maximum possible space with the given material.
Then the mathematician speaks up: "No, no, there's an even better way." To the others' amusement he proceeds to construct a little tiny fence around himself, then declares:
"I define myself to be on the outside."
Theorem: 1$ = 1c.
Proof:
And another that gives you a sense of money disappearing.
1$ = 100c
= (10c)^2
= (0.1$)^2
= 0.01$
= 1c
Here $ means dollars and c means cents. This one is scary in that I have seen PhD's in math who were unable to see what was wrong with this one. Actually I am crossposting this to sci.physics because I think that the latter makes a very nice introduction to the importance of keeping track of your dimensions.
Theorem: 1$ = 10 cent
Proof:
We know that $1 = 100 cents
Divide both sides by 100
$ 1/100 = 100/100 cents
=> $ 1/100 = 1 cent
Take square root both side
=> squr($1/100) = squr (1 cent)
=> $ 1/10 = 1 cent
Multiply both side by 10
=> $1 = 10 cent
: All positive integers are equal.
Proof: Sufficient to show that for any two positive integers, A and B, A = B.
Further, it is sufficient to show that for all N > 0, if A and B (positive integers) satisfy (MAX(A, B) = N) then A = B.
Proceed by induction.
If N = 1, then A and B, being positive integers, must both be 1. So A = B.
Assume that the theorem is true for some value k. Take A and B with MAX(A, B) = k+1. Then MAX((A-1), (B-1)) = k. And hence (A-1) = (B-1). Consequently, A = B.
Theorem: 4 = 5
Proof:
-20 = -20
16 - 36 = 25 - 45
4^2 - 9*4 = 5^2 - 9*5
4^2 - 9*4 + 81/4 = 5^2 - 9*5 + 81/4
(4 - 9/2)^2 = (5 - 9/2)^2
4 - 9/2 = 5 - 9/2
4 = 5
Theorem: log(-1) = 0
Proof:
a. log[(-1)^2] = 2 * log(-1)
On the other hand:
b. log[(-1)^2] = log(1) = 0
Combining a) and b) gives:
2* log(-1) = 0
Divide both sides by 2:
log(-1) = 0
"Psst, c'mere," said the shifty-eyed man wearing a long black trenchcoat, as he beckoned me off the rainy street into a damp dark alley. I followed.
"What are you selling?" I asked.
"Geometrical algebra drugs."
"Huh!?"
"Geometry drugs. Ya got your uppers, your downers, your sidewaysers, your inside-outers..."
"Stop right there," I interrupted. "I've never heard of inside-outers."
"Oh, man, you'll love 'em. Makes you feel like M.C. ever-lovin' Escher on a particularly weird day."
"Go on..."
"OK, your inside-outers, your arbitrary bilinear mappers, and here, heh, here are the best ones," he said, pulling out a large clear bottle of orange pills.
"What are those, then?" I asked.
"Givens transformers. They'll rotate you about more planes than you even knew existed."
"Sounds gross. What about those bilinear mappers?"
"There's a whole variety of them. Here's one you'll love -- they call it 'One Over Z' on the street. Take one of these little bad boys and you'll be on speaking terms with the Point at Infinity."
1. They speak only the Greek language.
2. They usually have long threatening names such as Bonferonni, Tchebycheff, Schatzoff, Hotelling, and Godambe. Where are the statisticians with names such as Smith, Brown, or Johnson?
3. They are fond of all snakes and typically own as a pet a large South American snake called an ANOCOVA.
4. For perverse reasons, rather than view a matrix right side up they prefer to invert it.
5. Rather than moonlighting by holding Amway parties they earn a few extra bucks by holding pocket-protector parties.
6. They are frequently seen in their back yards on clear nights gazing through powerful amateur telescopes looking for distant star constellations called ANOVA's.
7. They are 99% confident that sleep can not be induced in an introductory statistics class by lecturing on z-scores.
8. Their idea of a scenic and exotic trip is traveling three standard deviations above the mean in a normal distribution.
9. They manifest many psychological disorders because as young statisticians many of their statistical hypotheses were rejected.
10. They express a deap-seated fear that society will someday construct tests that will enable everyone to make the same score. Without variation or individual differences the field of statistics has no real function and a statistician becomes a penniless ward of the state.
Theorem: n=n+1
Proof:
(n+1)^2 = n^2 + 2*n + 1
Bring 2n+1 to the left:
(n+1)^2 - (2n+1) = n^2
Substract n(2n+1) from both sides and factoring, we have:
(n+1)^2 - (n+1)(2n+1) = n^2 - n(2n+1)
Adding 1/4(2n+1)^2 to both sides yields:
(n+1)^2 - (n+1)(2n+1) + 1/4(2n+1)^2 = n^2 - n(2n+1) + 1/4(2n+1)^2
This may be written:
[ (n+1) - 1/2(2n+1) ]^2 = [ n - 1/2(2n+1) ]^2
Taking the square roots of both sides:
(n+1) - 1/2(2n+1) = n - 1/2(2n+1)
Add 1/2(2n+1) to both sides:
n+1 = n
Theorem : All numbers are equal to zero.
Proof: Suppose that a=b. Then
a = b
a^2 = ab
a^2 - b^2 = ab - b^2
(a + b)(a - b) = b(a - b)
a + b = b
a = 0
Furthermore if a + b = b, and a = b, then b + b = b, and 2b = b, which mean that 2 = 1.
Theorem: 1 = 1/2:
Proof:
We can re-write the infinite series 1/(1*3) + 1/(3*5) + 1/(5*7) + 1/(7*9)
+...
as 1/2((1/1 - 1/3) + (1/3 - 1/5) + (1/5 - 1/7) + (1/7 - 1/9) + ... ).
All terms after 1/1 cancel, so that the sum is 1/2.
We can also re-write the series as (1/1 - 2/3) + (2/3 - 3/5) + (3/5 - 4/7)
+ (4/7 - 5/9) + ...
All terms after 1/1 cancel, so that the sum is 1.
Thus 1/2 = 1.
Theorem: 1 = -1
Proof:
1 = sqrt(1) = sqrt(-1 * -1) = sqrt(-1) * sqrt(-1) = 1^ = -1
Also one can disprove the axiom that things equal to the same thing are equal to each other.
1 = sqrt(1)
-1 = sqrt(1)
Therefore 1 = -1
As an alternative method for solving:
Theorem: 1 = -1
Proof:
x=1
x^2=x
x^2-1=x-1
(x+1)(x-1)=(x-1)
(x+1)=(x-1)/(x-1)
x+1=1
x=0
0=1
=> 0/0=1/1=1
Theorem: 1 + 1 = 2
Proof:
n(2n - 2) = n(2n - 2)
n(2n - 2) - n(2n - 2) = 0
(n - n)(2n - 2) = 0
2n(n - n) - 2(n - n) = 0
2n - 2 = 0
2n = 2
n + n = 2
or setting n = 1
1 + 1 = 2
Theorem: e=1
Proof:
2*e = f
2^(2*pi*i)e^(2*pi*i) = f^(2*pi*i)
e^(2*pi*i) = 1
Therefore:
2^(2*pi*i) = f^(2*pi*i)
2=f
Thus:
e=1
A shoeseller meets a mathematician and complains that he does not know what size shoes to buy. "No problem," says the mathematician, "there is a simple equation for that," and he shows him the Gaussian normal distribution. The shoeseller stares some time at het equation and asks, "What is that symbol?" "That is the Greek letter pi." "What is pi?" "That is the ratio between the circumference and the diameter of a circle." Upon this the shoeseller cries out: "What does a circle have to do with shoes?!"
There was this statistics student who, when driving his car, would always accelerate hard before coming to any junction, whizz straight over it , then slow down again once he'd got over it. One day, he took a passenger, who was understandably unnerved by his driving style, and asked him why he went so fast over junctions. The statistics student replied, "Well, statistically speaking, you are far more likely to have an accident at a junction, so I just make sure that I spend less time there."
Analysis:
1. Differentiate it and put into the refrig. Then integrate it in the refrig.
2. Redefine the measure on the referigerator (or the elephant).
3. Apply the Banach-Tarsky theorem.
Number theory:
1. First factorize, second multiply.
2. Use induction. You can always squeeze a bit more in.
Algebra:
1. Step 1. Show that the parts of it can be put into the refrig. Step 2. Show that the refrig. is closed under the addition.
2. Take the appropriate universal refrigerator and get a surjection from refrigerator to elephant.
Topology:
1. Have it swallow the refrig. and turn inside out.
2. Make a refrig. with the Klein bottle.
3. The elephant is homeomorphic to a smaller elephant.
4. The elephant is compact, so it can be put into a finite collection of refrigerators. That's usually good enough.
5. The property of being inside the referigerator is hereditary. So, take the elephant's mother, cremate it, and show that the ashes fit inside the refrigerator.
6. For those who object to method 3 because it's cruel to animals. Put the elephant's BABY in the refrigerator.
Algebraic topology:
Replace the interior of the refrigerator by its universal cover, R^3.
Linear algebra:
1. Put just its basis and span it in the refrig.
2. Show that 1% of the elephant will fit inside the refrigerator. By linearity, x% will fit for any x.
Affine geometry:
There is an affine transformation putting the elephant into the refrigerator.
Set theory:
1. It's very easy! Refrigerator = { elephant } 2) The elephant and the interior of the refrigerator both have cardinality c.
Geometry:
Declare the following:
Axiom 1. An elephant can be put into a refrigerator.
Complex analysis:
Put the refrig. at the origin and the elephant outside the unit circle. Then get the image under the inversion.
Numerical analysis:
1. Put just its trunk and refer the rest to the error term.
2. Work it out using the Pentium.
Statistics:
1. Bright statistician. Put its tail as a sample and say "Done."
2. Dull statistician. Repeat the experiment pushing the elephant to the refrig.
3. Our NEW study shows that you CAN'T put the elephant in the refrigerator.
|
Go to Page 1 2
|
|
.gif){kind=small}
