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3 replies to this topic

#1 TySim

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Posted 25 March 2008 - 06:27 PM

Being the math crazed maniac I was in school, one of my teachers challenged me to prove that 1=2.
Ok, so he said I would fail if I could not prove it....

3 months later I came upwith the solution....

Where is the Flaw?

A=B
A^2 = AB
A^2 - B^2 = AB - B^2
(A+B)(A-B) = B(A-B)
A+B = B
2B = B
2=1

What I did each step: (sorry forum not conducive to spaces)

A=B - Given
A^2 = AB - Multiplicative Property of Equality (A)
A^2 - B^2 = AB - B^2 - Additive Property of Equality (-B^2)
(A+B)(A-B) = B(A-B) - Evaluation
A+B = B - Reduction
2B = B - Substitution and Addition (since first statement say a=b)
2=1 - Reduction (by B)

The "^" means to the power of.


Spoiler for Clue

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#2 grey cells

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Posted 25 March 2008 - 06:36 PM

A=B
A^2 = AB
A^2 - B^2 = AB - B^2
(A+B)(A-B) = B(A-B)
A+B = B
2B = B
2=1


Spoiler for Flaw

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#3 Seventh Sage

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Posted 25 March 2008 - 07:27 PM

Being the math crazed maniac I was in school, one of my teachers challenged me to prove that 1=2.
Ok, so he said I would fail if I could not prove it....

3 months later I came upwith the solution....

Where is the Flaw?

A=B
A^2 = AB
A^2 - B^2 = AB - B^2
(A+B)(A-B) = B(A-B)
A+B = B
2B = B
2=1

What I did each step: (sorry forum not conducive to spaces)

A=B - Given
A^2 = AB - Multiplicative Property of Equality (A)
A^2 - B^2 = AB - B^2 - Additive Property of Equality (-B^2)
(A+B)(A-B) = B(A-B) - Evaluation
A+B = B - Reduction
2B = B - Substitution and Addition (since first statement say a=b)
2=1 - Reduction (by B)

The "^" means to the power of.


Spoiler for Clue



Spoiler for Flaw

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#4 rookie1ja

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Posted 25 March 2008 - 07:28 PM

What I did each step: (sorry forum not conducive to spaces)

A=B - Given
A^2 = AB - Multiplicative Property of Equality (A)
A^2 - B^2 = AB - B^2 - Additive Property of Equality (-B^2)
(A+B)(A-B) = B(A-B) - Evaluation
A+B = B - Reduction
2B = B - Substitution and Addition (since first statement say a=b)
2=1 - Reduction (by B)

The "^" means to the power of.

spaces can be kept in code tags ... like this ...
A=B								   - Given
A^2 = AB								   - Multiplicative Property of Equality (A)
A^2 - B^2 = AB - B^2						   - Additive Property of Equality (-B^2)
(A+B)(A-B) = B(A-B)							   - Evaluation 
A+B = B								   - Reduction
2B = B								   - Substitution and Addition (since first statement say a=b)
2=1								   - Reduction (by B)

"power of" can be easily used as "super-script" ... eg. A2 = AB

both code and super-script are buttons when you write posts

and I almost forgot ... already posted in a few variations ... check this

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