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#1 2009-10-20 20:36:32

saundo
Member
Registered: 2009-10-20
Posts: 8

proof that 2=2.82 thus that algebra has a huge fault

i have proven not that 1=2 but that 2=3.41 i am only 16 but im pretty sure there are no faults in this. what i did and expalnations on how are written below
x=2 y=2
x=y
x^2=y+x
√(x^2 )=√(y)+(x)
x=1.41+x
2=1.41+2
2=3.14
line1  x=2 y=2
line 2 therefore x=y
line 3 add x to both sides( since x=2 and 2+2 Is  the same as 2^2 it become x^2)
line 4 square root both sides of the equation
line 5 we are left with x=1.41+x because √2 is 1.41 to 2 decimal places
line 6 substitute the pro-numeral x with the its value (2) leaves us with 2=1.41+2
line 7 the answer is 2=3.41
find any faults now?

Last edited by saundo (2009-10-21 00:44:46)

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#2 2009-10-20 21:19:53

dannyv
Member
Registered: 2007-09-20
Posts: 34

Re: proof that 2=2.82 thus that algebra has a huge fault

the problem is between line4 and 5. You cannot distribute the square root, i mean,

To my knowledge there is no way to decompose a square root

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#3 2009-10-20 23:26:06

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,560

Re: proof that 2=2.82 thus that algebra has a huge fault

I removed a rude comment

Nice try, saundo, but Algebra still wins smile


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

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#4 2009-10-21 00:34:18

saundo
Member
Registered: 2009-10-20
Posts: 8

Re: proof that 2=2.82 thus that algebra has a huge fault

dannyv wrote:

the problem is between line4 and 5. You cannot distribute the square root, i mean,

To my knowledge there is no way to decompose a square root

for some reason the brackets did not come up properly

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#5 2009-11-22 03:51:16

simplyjasper
Member
Registered: 2009-11-15
Posts: 24

Re: proof that 2=2.82 thus that algebra has a huge fault

3rd line itself is wrong...
If y = x,

x + y = 2x or 2y not x^2

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#6 2009-11-22 19:39:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 94,538

Re: proof that 2=2.82 thus that algebra has a huge fault

Hi;

For x=2 and y=2 as he states in line 1:

You can say x + y = x^2.


In mathematics, you don't understand things. You just get used to them.

If it ain't broke, fix it until it is.

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#7 2010-05-17 08:32:52

DaveRobinsonUK
Member
Registered: 2010-04-24
Posts: 123

Re: proof that 2=2.82 thus that algebra has a huge fault

Hi Saundo

Are you using a calculator? If so are you pressing the equals sign when you add x+y or entering x then add then y
then the sqrt.

I get 1.4142136, which is the approximation of the sqrt(2) and when I then press = I get 3.4142136

The reason for this is that calculators and programming languages evaluate certain operations before others
usually following the BIDMAS rules. Since SQRT() is a division operation it would be evaluated first on the
associated number, which is 2.

If you have a bracket function, you should get 2. The correct answer should be (+/-2)


Can feel it coming together.. Slowly but Surely smile

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#8 2010-10-26 14:41:31

thewordalive
Member
Registered: 2010-09-27
Posts: 4

Re: proof that 2=2.82 thus that algebra has a huge fault

MathsIsFun wrote:

I removed a rude comment

Algebra still wins smile

algebra wins, but geometry pwns >:]

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