2013 CSSA Mathematics Thoughts? (1 Viewer)

RealiseNothing

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When will you people realise. An infinite sum, is a sum (defined) as n goes to infinite. Lol how is that even a question. An infinite sum. Not an infinite infinite
Basically this, regardless of whether or not it converges to some real value it is an infinite sum, so I'm curious as to what the question is actually asking.
 

bedpotato

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Basically this, regardless of whether or not it converges to some real value it is an infinite sum, so I'm curious as to what the question is actually asking.
Something like "for what values of y does this series NOT have an infinite sum"...
 

wagig

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It was 1 - y cause i remember finding it weird to expand lol
 

RealiseNothing

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1, y^2/(y-1)^2, y^4/(y-1)^4...
y =/= 0 and y =/= 1.

Edit: Was it (1-y) and not (y-1)? Sorry.
Well technically an infinite sum is just an expression with an infinite amount of terms. Whether of not the series given has an infinite amount of terms is independent of the value of 'y' and actually dependent on the powers of the series.

But I get the feeling they want you to find the values of 'y' such that it converges to some finite value and not infinity. Did the question say infinite sum exactly, or did it maybe say "sum of infinity" or some variation of this.
 

iBibah

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Well technically an infinite sum is just an expression with an infinite amount of terms. Whether of not the series given has an infinite amount of terms is independent of the value of 'y' and actually dependent on the powers of the series.

But I get the feeling they want you to find the values of 'y' such that it converges to some finite value and not infinity. Did the question say infinite sum exactly, or did it maybe say "sum of infinity" or some variation of this.
I was going to say, they must have taken the wrong definition and thought they sounded smart by trying to trick people. But I guess they can do that because the term 'sum to infinity' was never defined last year, so I would have treated it as a limiting sum nevertheless, even though its ethnically wrong.
 

bedpotato

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Well technically an infinite sum is just an expression with an infinite amount of terms. Whether of not the series given has an infinite amount of terms is independent of the value of 'y' and actually dependent on the powers of the series.

But I get the feeling they want you to find the values of 'y' such that it converges to some finite value and not infinity. Did the question say infinite sum exactly, or did it maybe say "sum of infinity" or some variation of this.
Infinite sum exactly.
Not 100% sure though, but most likely (99% sure) it did say "infinte sum".
 

RealiseNothing

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I was going to say, they must have taken the wrong definition and thought they sounded smart by trying to trick people. But I guess they can do that because the term 'sum to infinity' was never defined last year, so I would have treated it as a limiting sum nevertheless, even though its ethnically wrong.
hahahahahahahahhahahahha
 

iBibah

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Haha bro this iPads autocorrect is posing me off so much


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Son of a bitch *PISSING


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RealiseNothing

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Infinite sum exactly.
Not 100% sure though, but most likely (99% sure) it did say "infinte sum".
If they did I'm pretty sure then that the question is ~technically~ wrong. Unless the answer they are looking for is "the value of y doesn't matter".
 

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