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# 2=1 ?!?!?!

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1. Explain:

a=b
a^2=ab
2a^2=a^2+ab
2a^2-2ab=a^2-ab
2(a^2-ab)=(a^2-ab)
2=1
?????

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2. a^2 - ab = 0 by a = b.
3. this is OLD AND DEAD!
4. Wow. You broke Maths. You are now the indisputed master of the universe. How does it feel?
5. I'm amazed people never get tired of this.
6. You cannot divide by 0.

Using variables, it would work.

Using real numbers, it will not work.
7. lol i still love that proof even though it isn't really a proper proof it confuses people quite a bit - but it does show why you shouldn't divide by 0

8. TROLL
9. omg 1.999999999999999999999999999999 9999999999 =2 omg
10. (Original post by tamimi)
omg 1.999999999999999999999999999999 9999999999 =2 omg
No, it doesn't.
1.999.... = 2
11. (Original post by Instincts_2012)
You cannot divide by 0.

Using variables, it would work.

Using real numbers, it will not work.
I don't understand what you mean by 'using variables, it would work'. You can't divide by a variable which potentially takes the value of zero without branching your reasoning into "either <expression> = 0 or <everything from dividing by the expression onwards>".
12. (Original post by Trollin)
No, it doesn't.
1.999.... = 2
13. (Original post by tamimi)
Guilty as charged. But seriously, the pedantry of mathematicians knows no bounds :P
14. (Original post by tamimi)
does equal

But what the OP has written is nonsense!
15. (Original post by raheem94)
does equal

But what the OP has written is nonsense!
I know that is widely accepted but I just can't see it that way. Wouldn't it be true saying:

That's just my thought. But then again, the infinity fraction tends to zero... However that doesn't mean it shouldn't be there.
16. (Original post by Micky76)
I know that is widely accepted but I just can't see it that way. Wouldn't it be true saying:

That's just my thought. But then again, the infinity fraction tends to zero... However that doesn't mean it shouldn't be there.
I can't say much about it.

17. (Original post by As_Dust_Dances_)
You've just assumed a equals b and that's like saying c also equals d which isn't the case!
Lol what?
18. (Original post by Slumpy)
I'm amazed people never get tired of this.
because nobody stops for a second and thinks, they just get overwhelmed by the sheer plausibility and why nobody has seen it yet
19. Trifling!
20. this doesn't work with 0 values a good example is 2x=x (/x) 2=1 2x-x=0 x=0.In the above proof a^2-ab=0 because it is equal to aa-aa=0 and 2 times that will equal 1 times that.

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