# Thread: 2+2 Does not equal 4... Really..

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## 2+2 Does not equal 4... Really..

Not a joke, not a riddle.

----
2+2 does not equal 4

The above is correct in most instances.

There is only one exception.

Which one?

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## Re: 2+2 Does not equal 4... Really..

Do you mean...

----------------------
2+2 DOES equal 4.
The above is correct for most instances.

There is only one exception.

Which one?
----------------------

I can think of an instance where 2+2 != 4.

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"Reality is optional"

The other option is plain stupidity

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erm in base 3?

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Here's one exception where 2 + 2 != 4:

In scalar addition, 2+2 is 4.

In vector addition, 2+2 may equal (0<=X<=4).

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yeah.. in electronics there are many cases like that
If the 2 is on the J scale, then its 2 +J2
or if its current, and 2a-> and <-2a then 2+2=0

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Ahh. Some of you are getting very close, however not completely on the ball yet. I did mean what I said when in most instances it is NOT 4. In scalar addition 2+2 does not equal 4. It is a matter of first level rounding.

For example:
1/3 of a unit, in a rational form is 0.33333333333333333333333... so the statement of.

.333333333333333333... x 12 = 2 + 2 is true.

2 + 2 = 4 with or without first level rounding

That is not the case of the rational form let's look it with a microscope 0.33333333333333333333... x 12 = 3.9999999999999999999996 and that 6 is the one that proved that under the microscope 2 + 2 is not really 4 .

SO I still pose the question. When does 2+2 equal 4 in an exact science?

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Right.. but you said that 1/3 * 12 is not 4
you didnt prove that 2 + 2 is not equal to 4

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1/3 * 12 mathematically equals two + two. In math, if you can prove something is equal to something, which you can do with the above, then it sets a precedent, and everything that one side of the equation is equal to, so must be the other side.

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That is just one example however. There are many others. Look at polyploids.

Or even Donald J. Wheeler, Ph.D.
http://www.spcpress.com/ink_pdfs/wh_two_plus_two.htm analysis of the topic.

The answer is quite easy, and believe it or not, the person who came the closest is the quote that 4 degrees made.

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Originally posted by p[]

That is not the case of the rational form let's look it with a microscope 0.33333333333333333333... x 12 = 3.9999999999999999999996
No it doesn't.

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This reminds me of the .99999999999999... !=1 thing. It does. Theres a whole calculus equation. 0.333333333333...... x 12 = 4. It does. I swear to you, it does.

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Originally Posted by Hans de Vreught
0.9999... = 1

Choose 0.9999... = sum_(n = 1)^(oo) (9)/(10^n) = lim_(m --> oo) sum_(n
= 1)^m (9)/(10^n) . Suppose varepsilon > 0 , thus delta = 1/- log_(10)
varepsilon . For every varepsilon = 10^(-1/delta) we have that

m > 1/delta

So by the \left| sum_(n = 1)^m (9)/(10^n) - 1 \right| = (1)/(10^m) <
(1)/(10^(1/delta)) = varepsilon definition of the limit we have

varepsilon - delta

Not formal enough? In that case you need to go back to the
construction of the number system. After you have constructed the
reals (Cauchy sequences are well suited for this case, see
[Shapiro75]), you can indeed verify that the preceding proof correctly
shows lim_(m --> oo) sum_(n = 1)^m (9)/(10^n) = 1 .

An informal argument could be given by noticing that the following
sequence of natural'' operations has as a consequence 0.9999... = 1
. Therefore it's natural'' to assume 0.9999... = 1 .

0.9999... = 1

Thus x = 0.9999... ; 10x = 10 o 0.9999... ; 10x = 9.9999... ; 10x - x
= 9.9999... - 0.9999... ; 9x = 9 ; x = 1 ; .

An even easier argument multiplies both sides of 0.9999... = 1 by
0.3333... = 1/3 . The result is 3 .

Another informal argument is to notice that all periodic numbers such
as 0.9999... = 3/3 = 1 are equal to the period divided over the same
number of 0.46464646... s. Thus 9 . Applying the same argument to
0.46464646... = 46/99 .
And in even better notation, click here.
Last edited by Xshare; 03-31-2004 at 09:18 PM.

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2 + 2 = 5
for extremely large values of 2

Those who spend their lives dwelling in the abstract are well aware of this maxim. If one is convinced that 2 + 2 = 5, then that is proof alone. Are we right? Probably not. Or is this some sort of Gestalt 'whole greater than the sum of its parts' equation designed by motivational speakers for a 'conceptual breakthrough?' Probably not. Is it a song by Radiohead? Yes, this much we can establish.

"Well, now I know where all the departed quantities went to -- the right-hand side of this equation."
-- Bishop Berkeley
source: http://www.thinkgeek.com/tshirts/generic/60f5/

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2 apples + 2 apples = 4 apples... the rest is just horse apples

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Originally posted by ilyash
Right.. but you said that 1/3 * 12 is not 4
you didnt prove that 2 + 2 is not equal to 4
My question is related to the above...

where does the 1/3 * 12 come from... when we're talking solid scalar 2 + 2 = 4?

When I think of the value of a 2, I only think about the completely solid 2.000000(c). I would never think of 2 as a division of a smaller fraction.

It would have been a bit different if you inquired about the floating point format of 2 like 2. + 2. != 4. as the floating point notation shows there may or may not be an insignificant value there somewhere.

It's just a radical way of mathematical evaluation - stating the most obvious that the general population neglects because most prefer the solid 2

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## Re: 2+2 Does not equal 4... Really..

Originally posted by p[]
Not a joke, not a riddle.

----
2+2 does not equal 4

The above is correct in most instances.

There is only one exception.

Which one?
I can think of a few exceptions. 2 + 2 equals 4 unless:
You are a moron
You are high
You got hit in the head really hard
Last edited by John[H4Y]; 04-01-2004 at 04:57 AM.

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