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#1 2006-04-25 22:43:41

saarvin89
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1+1=1

please proof for tat tis is true

#2 2006-04-25 23:25:40

Patrick
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Re: 1+1=1

I guess this is a joke? smile


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#3 2006-04-26 00:57:39

ganesh
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Re: 1+1=1

-1=1
(1-2) = (2-1)
Taking square root on both the sides,
1-2=2-1
2=4
Dividing both the sides by 2,
1=2.
But we know 1+1=2,
Therefore,
1=1+1
or
1+1=1 big_smile


Character is who you are when no one is looking.

#4 2006-05-01 02:29:44

coolwind
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Re: 1+1=1

ganesh wrote:

-1=1
(1-2) = (2-1)
Taking square root on both the sides,
1-2=2-1
2=4
Dividing both the sides by 2,
1=2.
But we know 1+1=2,
Therefore,
1=1+1
or
1+1=1 big_smile

cool...cool

#5 2006-05-01 19:35:09

naturewild
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Re: 1+1=1

That's... smart!

#6 2006-05-01 21:14:05

MathsIsFun
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Re: 1+1=1

That's ... ganesh!


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

#7 2006-05-01 22:14:47

krassi_holmz
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Re: 1+1=1

(1-2) = (2-1)
Taking square root on both the sides,
1-2=2-1

Noooo...:

a^2=b^2 => |a|= |b|, not a=b.

Last edited by krassi_holmz (2006-05-01 22:15:14)


IPBLE:  Increasing Performance By Lowering Expectations.

#8 2006-05-06 03:26:30

luca-deltodesco
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Re: 1+1=1

ok then, how about this false proof

-1/1 = 1/-1
sqrt(-1/1) = sqrt(1/-1)
sqrt(-1)/sqrt(1) = sqrt(1)/sqrt(-1) or..
i/1 = 1/i
i/2 = 1/(2i)
i/2 + 3/(2i) = 1/(2i) + 3/(2i)
i (i/2 + 3/(2i) ) = i ( 1/(2i) + 3/(2i) )
(i^2)/2 = (3i)/2i = i/(2i) + (3i)/(2i)
(-1)/2 + 3/2 = 1/2 + 3/2
-1/2 = 1/2
-1 = 1


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#9 2006-05-06 14:06:17

ganesh
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Re: 1+1=1

luca-deltodesco wrote:

ok then, how about this false proof

-1/1 = 1/-1
sqrt(-1/1) = sqrt(1/-1)
sqrt(-1)/sqrt(1) = sqrt(1)/sqrt(-1) or..
i/1 = 1/i

There lies the mistake.
As krassi_holmz rightly pointed out in the previous post,
If


then

or

It would not be right to say a=b.
When square root is being taken on both sides of an equation, the plus or minus/minus or plus sign has an important role to play, it cannot be overlooked.
When you had taken the square roots of the LHS and the RHS in steps 2, 3, you have taken only the positive values. Remember square root on 1 is not +1 alone, it is 1.


Character is who you are when no one is looking.

#10 2006-05-06 17:37:17

krassi_holmz
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Re: 1+1=1

Good explamation.


IPBLE:  Increasing Performance By Lowering Expectations.

#11 2006-05-06 18:28:32

Affirmation
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Re: 1+1=1

x=y
x*x = y*y
x*y = y*y | - x*x
x*y - x*x = y*y - x*x
x(y-x) = (y-x)*(y+x) | /(y-x)
x = y + x
x = x + x
x = 2x
1 = 2

#12 2006-05-06 20:13:40

ganesh
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Re: 1+1=1

Affirmation wrote:

x(y-x) = (y-x)*(y+x) | /(y-x)

The (erroneous) proof started with x=y.
Hence, x-y=0 and y-x=0.
The two sides of an equation should not be divided by zero, it may lead to absurd results!


Character is who you are when no one is looking.

#13 2006-05-07 00:40:54

Affirmation
Guest

Re: 1+1=1

Correct smile Of course there will always be something wrong as 1 cannot equal 2 tongue

#14 2006-05-07 10:08:35

MathsIsFun
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Re: 1+1=1

We had another collection of false proofs somewhere here - maybe I should collect them and make a page about it.


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

#15 2006-05-10 10:03:19

John E. Franklin
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Re: 1+1=1

1 will not equal 2 as long as we judge them to be different.


igloo myrtilles fourmis

#16 2006-05-10 11:09:04

Ricky
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Re: 1+1=1

1 = 2 in mod 0.


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