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### #1

Posted 15 January 2008 - 07:04 AM

a = b

aa = ab

aa - bb = ab - bb

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

a + b = b

a + a = a

2a = a

2 = 1

### #2

Posted 15 January 2008 - 07:09 AM

*The greatest challenge to any thinker is stating the problem in a way that will allow a solution.*

- Bertrand Russell

### #3

Posted 25 January 2008 - 08:40 PM

to........a + a = a

the top line just means a=0?

### #4

Posted 26 January 2008 - 09:34 PM

aargh confusing much ??

### #5

Posted 26 January 2008 - 10:46 PM

how do you go from.........a + b = b

to........a + a = a

the top line just means a=0?

Because a = b, he can substitute a and b freely for each other.

### #6

Posted 29 January 2008 - 09:03 PM

The following is what seems to be a mathematical proof that two equals one. What's wrong with it?

a = b

aa = ab

aa - bb = ab - bb

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

a + b = b

a + a = a

2a = a

2 = 1

The problem is with the division in the fourth line. You have to divide each element on the left side of the equation by (a-b). The fifth line should be (a+b)/(a-b)=b

### #7

Posted 30 January 2008 - 02:33 PM

The problem is with the division in the fourth line. You have to divide each element on the left side of the equation by (a-b). The fifth line should be (a+b)/(a-b)=b

You got it wrong, brother. The division was ok in a sense, you divide both the left and right sides by the same number other than zero. The problem here is dividing both sides -- the left and right sides -- by zero. From basic maths we know that when a number is divided by zero, it would be undefined.

### #8

Posted 30 January 2008 - 04:00 PM

I'll bet Aunt Minta is probably aYou got it wrong,

brother. The division was ok in a sense, you divide both the left and right sides by the same number other than zero. The problem here is dividing both sides -- the left and right sides -- by zero. From basic maths we know that when a number is divided by zero, it would be undefined.

**sista**.

*The greatest challenge to any thinker is stating the problem in a way that will allow a solution.*

- Bertrand Russell

### #9

Posted 30 January 2008 - 05:24 PM

I'll bet Aunt Minta is probably a

sista.

Thanx Bonanova, I agree. I just didn't notice the name.

What do you think the odds would be that Auntie is a man?

**Edited by brhan, 30 January 2008 - 05:27 PM.**

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