Difference between revisions of "1992 OIM Problems/Problem 2"

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== Solution ==
 
== Solution ==
[[File:1992_OIM_P2.png|center|600px]]
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[[File:1992_OIM_P2a.png|center|600px]]
  
 
* Note.  I actually competed at this event in Venezuela when I was in High School representing Puerto Rico.  I got a ZERO on this one because I didn't even know what was I supposed to do, nor did I know what the sum of the lengths of the intervals, disjoint two by two meant.  A decade ago I finally solved it but now I don't remember how.  I will attempt to solve this one later.
 
* Note.  I actually competed at this event in Venezuela when I was in High School representing Puerto Rico.  I got a ZERO on this one because I didn't even know what was I supposed to do, nor did I know what the sum of the lengths of the intervals, disjoint two by two meant.  A decade ago I finally solved it but now I don't remember how.  I will attempt to solve this one later.

Revision as of 10:57, 17 December 2023

Problem

Given the collection of $n$ positive real numbers $a_1 < a_2 < a_3 < \cdots < a_n$ and the function:

\[f(x) = \frac{a_1}{x+a_1}+\frac{a_2}{x+a_2}+\cdots +\frac{a_n}{x+a_n}\]

Determine the sum of the lengths of the intervals, disjoint two by two, formed by all $f(x) = 1$.

~translated into English by Tomas Diaz. ~orders@tomasdiaz.com

Solution

1992 OIM P2a.png
  • Note. I actually competed at this event in Venezuela when I was in High School representing Puerto Rico. I got a ZERO on this one because I didn't even know what was I supposed to do, nor did I know what the sum of the lengths of the intervals, disjoint two by two meant. A decade ago I finally solved it but now I don't remember how. I will attempt to solve this one later.

Alternate solutions are always welcome. If you have a different, elegant solution to this problem, please add it to this page.

See also

https://www.oma.org.ar/enunciados/ibe7.htm