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#1 2009-10-21 00:46:50

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

second try 2=3.41

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?

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#2 2009-10-21 00:54:36

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: second try 2=3.41

Hi saundo;

line 4 to 5 is incorrect. When you take the square root of both sides in line 4 you should get:

√(x^2 )=√(y+x)


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2009-10-21 01:02:45

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

Re: second try 2=3.41

bobbym wrote:

Hi saundo;

line 4 to 5 is incorrect. When you take the square root of both sides in line 4 you should get:

√(x^2 )=√(y+x)

that is why they were seperate √(y)+(x)

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#4 2009-10-21 01:08:43

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: second try 2=3.41

Hi saundo;

But you cannot separate them. The rules of algebra have to be adhered to.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#5 2009-10-21 01:13:51

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

Re: second try 2=3.41

bobbym wrote:

Hi saundo;

But you cannot separate them. The rules of algebra have to be adhered to.

im pretty sure there is another rule that what you do too 1 side you do to all parts of the other which means that √x^2=√y+√x thus proving my first equation 2=2.82 correct

Last edited by saundo (2009-10-21 01:15:28)

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#6 2009-10-21 01:21:37

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: second try 2=3.41

Hi saundo;

Sorry, I wished that were true. Would make a lot of my work more meaningful. Unfortunately it is not, this is correct:

√(x^2 )=√(y+x)

this is not:

√x^2=√y+√x

Last edited by bobbym (2009-10-21 01:21:58)


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#7 2009-10-21 01:25:55

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

Re: second try 2=3.41

bobbym wrote:

Hi saundo;

Sorry, I wished that were true. Would make a lot of my work more meaningful. Unfortunately it is not, this is correct:

√(x^2 )=√(y+x)

this is not:

√x^2=√y+√x

ah i didnt put those brakets in but try these                         
x=2 y=2
x=y
x^2=y+x
√x^2 =√y+x
x=1.41+1.41
x=2.82
2=2.82

or

x=2 y=2
x=y
x^2=y+x
√x^2 =√y+x
x=1.41+1.41
x=2.82
1.41=2.82

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#8 2009-10-21 01:30:26

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: second try 2=3.41

Hi saundo;

√x^2 =√y+x this is also incorrect. What you do to one side you must do to the other side of an equation.

√(x^2) =√(y+x) is correct. Surely you know that 2 does equal 2.82. If I gave you 2 dollars would you give me 2.82 back? The fact that you are getting this contradiction proves that √x^2 =√y+x is incorrect.

Last edited by bobbym (2009-10-21 01:31:24)


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#9 2009-10-21 01:37:54

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

Re: second try 2=3.41

hi bobbym
It's ok i understand now but im happy i got as as close as i did since i havent finished high school yet
but thank you for pointing out the flaw now that i know it i can see if my teacher believes it and if my teacher can point out the flaw.:P
thanks anyway bobbym
p.s if you gave me two dollars i would prove in a practical way that 2 = 0 tongue

Last edited by saundo (2009-10-21 01:38:55)

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#10 2009-10-21 01:41:42

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: second try 2=3.41

Hi saundo;

Yes, I know how to prove that 2 = 0 in that case. Glad to help!


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

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