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# Infinte sum watch

1. What is the sum of the infinte series:

1 - 1 + 1 - 1 + 1 - ...

?
2. (Original post by mikesgt2)
What is the sum of the infinte series:

1 - 1 + 1 - 1 + 1 - ...

?
We can say that the sum is (1-1) + (1-1) + (1-1) + (1-1)...
Which of course (1-1)=0, so it is like saying 0+0+0+0+0....
which is 0.

BUT, we can also say that 1 + (-1+1) + (-1+1) + (-1+1)....which means that it would be 1+ 0 +0 + 0 + 0 + 0 + 0...which is 1.

Since both calculations give the same answer we can assume that 0 = 1.

However why 2 different answers? Well since infinity has no defined value then the question itself is fallicious, so the answer you get is fallicious.
3. (Original post by 2776)
We can say that the sum is (1-1) + (1-1) + (1-1) + (1-1)...
Which of course (1-1)=0, so it is like saying 0+0+0+0+0....
which is 0.

BUT, we can also say that 1 + (-1+1) + (-1+1) + (-1+1)....which means that it would be 1+ 0 +0 + 0 + 0 + 0 + 0...which is 1.

Since both calculations give the same answer we can assume that 0 = 1.

However why 2 different answers? Well since infinity has no defined value then the question itself is fallicious, so the answer you get is fallicious.
Anyone agree with me?
4. (Original post by 2776)
Anyone agree with me?
Yes. Spot on.
5. (Original post by 2776)
Anyone agree with me?
6. (Original post by elpaw)
7. (Original post by Ralfskini)
Is it in the latest issue?
8. (Original post by ditzy blonde)
Is it in the latest issue?
no it was from early october i think, cant remember exactly
9. (Original post by 2776)
We can say that the sum is (1-1) + (1-1) + (1-1) + (1-1)...
Which of course (1-1)=0, so it is like saying 0+0+0+0+0....
which is 0.

BUT, we can also say that 1 + (-1+1) + (-1+1) + (-1+1)....which means that it would be 1+ 0 +0 + 0 + 0 + 0 + 0...which is 1.

Since both calculations give the same answer we can assume that 0 = 1.

However why 2 different answers? Well since infinity has no defined value then the question itself is fallicious, so the answer you get is fallicious.
Yup, I agree. But there is another possibility:

Let the sum of the series be x

We can say that: x = 1 - x
=> 2x = 1
x = 1/2

I think you could also argue that x = -1/2

This was just an interesting thing I found in a book about infinity.
10. A baby could have worked that sum out! I don't know, Maths these days is getting easier and easier.
11. (Original post by elpaw)
no it was from early october i think, cant remember exactly
27th September. I'm a little behind.
12. (Original post by Ralfskini)
27th September. I'm a little behind.
your clock is running faster than mine. maybe i've been on some light speed travel lately.

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