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#1 2009-10-21 19:36:32

saundo
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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 23:44:46)

 

#2 2009-10-21 20:19:53

dannyv
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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

 

#3 2009-10-21 22:26:06

MathsIsFun
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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
 

#4 2009-10-21 23:34:18

saundo
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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

 

#5 2009-11-23 02:51:16

simplyjasper
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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

 

#6 2009-11-23 18:39:28

bobbym
Administrator

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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.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#7 2010-05-18 06:32:52

DaveRobinsonUK
Full Member

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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
 

#8 2010-10-27 13:41:31

thewordalive
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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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