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# 1 = 2 anyone? watch

1. Anyone know any decent proofs for 1 = 2?

I'd especially like to see some without dividing by 0, or if anyone knows any using cyclical functions would be good - I'm sad and spend my time finding such proofs.

Put down any you know anyway!

Cheers guys!
2. (Original post by Master Gee)
Anyone know any decent proofs for 1 = 2?

I'd especially like to see some without dividing by 0, or if anyone knows any using cyclical functions would be good - I'm sad and spend my time finding such proofs.

Put down any you know anyway!

Cheers guys!
suppose x = 1
then x ² - 1 = x - 1
factorising gets you (x + 1) (x - 1) = (x - 1)

Divide both side by (x-1)
you get (x+1) = 1

put back x = 1

and you get 2 = 1

=)
3. (Original post by Master Gee)
Anyone know any decent proofs for 1 = 2?

I'd especially like to see some without dividing by 0, or if anyone knows any using cyclical functions would be good - I'm sad and spend my time finding such proofs.

Put down any you know anyway!

Cheers guys!
1=a
let a=2
1=2

How can you have proof for something that's not true
4. (Original post by Saiyan)
Divide both side by (x-1)
bogus! you *cant* divide by 0
5. (Original post by endeavour)
1=a
let a=2
1=2

How can you have proof for something that's not true
With cunning and deception!

Obviously you can't, but it's a laugh trying. Prooving that 1 = 2 kind of negates the universe because it means all numbers equal each other so everything dies.

Most of the proofs revolve around 0 and it's lack of definition - division by 0, powers of 0, 0 to a power etc. There's other ones too such as using set theory or cyclical function as I said above.
6. imagine a series x+x+x+x+x+x+x+x...+x
differentiated u get 1+1+1+1+...1
ok, now say you have x 1's
which is x
that means you would x x's
which is x^2
differentiated you get 2x
so the answer is x and 2x
regardless of the value of x
therefore 1=2
7. pretty damn good, although if you know how it works could you explain how it goes from the third to the fourth line.

the - 2(1/2 + 1/4 +...) going to -(1 + 1/2 + 1/3 + ...) is what i don't get

Cheers
8. (Original post by Freeway)
imagine a series x+x+x+x+x+x+x+x...+x
differentiated u get 1+1+1+1+...1
ok, now say you have x 1's
which is x
that means you would x x's
which is x^2
differentiated you get 2x
so the answer is x and 2x
regardless of the value of x
therefore 1=2
that one's a good un too, although it only works for positive integers and there's another reason why it's wrong too... I've forgotten it though
9. (Original post by Master Gee)
pretty damn good, although if you know how it works could you explain how it goes from the third to the fourth line.

the - 2(1/2 + 1/4 +...) going to -(1 + 1/2 + 1/3 + ...) is what i don't get

Cheers
2(1/2 + 1/4 +...) = 2/2 + 2/4 + 2/6 + 2/8 ... = 1 + 1/2 + 1/3 + 1/4 ...
10. (Original post by endeavour)
1=a
let a=2
1=2

How can you have proof for something that's not true
lol
11. If you wanted to know, the log 2 one is false because the series is not absolutely convergent, and the series one is because the function is not continuous.
12. (Original post by JamesF)
2(1/2 + 1/4 +...) = 2/2 + 2/4 + 2/6 + 2/8 ... = 1 + 1/2 + 1/3 + 1/4 ...
cough... that's embarassing

cheers
13. (Original post by El Chueco)
bogus! you *cant* divide by 0
-____-" lol... thanks for pointing that out for me =)
14. Hmm i did have a 1=9 written down somewhere but i've lost it. Had loads of trig in it, but wasn't technically quite right! Does anyone know it??
15. http://www.magicmaths.tk

The one on the left is fairly rubbish, but the one on the right is a little better.
16. a = b
times both sides by b
ab = b2
minus a2
ab – a2 = b2 – a2
factorise
a(b-a) = (b+a)(b-a)
divide by (b-a)
a = b+a
replace b by a
a = a + a
a = 2a
divide by a
1 = 2

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