BrainDen.com - Brain Teasers
• 0 # 2=1 How can this be true? read to find out

## Question a=b

a2=ab

a2-b2=ab-b2

9a+b)(a-b)=b(a-b)

(a+b)=b

a+a=a

2a=a

2=1

To be honest I didn't really come up with this i found it on another bwesite but it is awesome right? Take that math teachers!

## Recommended Posts

• 0

Reposting it to make it a little bit easier to understand:

a=b

a2=ab

a2-b2=ab-b2

(a+b)(a-b)=b(a-b)

a+b=b

a+a=a

2a=a

2=1

I have found the flaw, but I remember when I posted that 1+1=0 and someone ticked me off by posting the flaw. It made me so sad that someone would go and ruin the fun. So I'm not gonna post it! ##### Share on other sites
• 0 I, however, have no problem posting the flaw:

<p>if a=b, then a-b=0</p><p>From line 4 to line 5 you divide by (a-b), which is dividing by zero. This is not allowed.</p>

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• 0 a=b

a2=ab

a2-b2=ab-b2

9a+b)(a-b)=b(a-b)

(a+b)=b

a+a=a

2a=a

2=1

To be honest I didn't really come up with this i found it on another bwesite but it is awesome right? Take that math teachers!

If your math teacher takes more than 30 seconds to see the error, get another math teacher!

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• 0

without even reading: the flaw is division by 0

after reading: you divided the 4th line by a-b and since a=b no need to go futher

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• 0

This reminds me a bit of when we did systems of equations/inequalities in math class and we got nonsense like 7=5 or 0>11 when there was no solution.

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• 0 DIVIDE BY ZERO EXCEPTION

a=b => a-b=0

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• 0 DIVIDE BY ZERO EXCEPTION

a=b => a-b=0

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• 0 a=b

a2=a+b (not a2=ab because ab would be equal to "a" raised to the second power).

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• 0

@Nan That's what he's saying. I reposted it right below with the correct exponents so it's easier to read. ##### Share on other sites
• 0 Our science teacher tried that same trick on us.

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