## count it

For students of class 11-12 (age 16+)
Rafe
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### count it

$\frac{n+y}{n}$ is an integer for some integer value of $n$ while $y$ is an integer.find the summation of the value of all $n$
Last edited by sourav das on Sun Jan 06, 2013 8:30 pm, edited 1 time in total.
Reason: LaTeXed

SANZEED
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### Re: count it

Write $\frac{n+y}{n}=1+\frac{y}{n}$ so $n$ must divide $y$. Thus sum of the values of all $n$ is actually the sum of divisors of $y$.
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### Re: count it

@ SANZEED, Rafe has said $n\in Z$, not $n\in N$.
If $a$ divides $y$, then $-a$ also divides $y$. Hence summation of all values of $n$ is $0$.

In my pc, I am not seeing \mathbb characters. Is it happening also to you? If is, then I think the file 'AMSmath.js' has been damaged in this server. We should inform it to Moon Vai immediately.
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*Mahi*
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### Re: count it

Phlembac Adib Hasan wrote:In my pc, I am not seeing \mathbb characters. Is it happening also to you? If is, then I think the file 'AMSmath.js' has been damaged in this server. We should inform it to Moon Vai immediately.
No, all \mathbb symbols are loading alright in my PC. You might try clearing your jsMath cache.

Use $L^AT_EX$, It makes our work a lot easier!