MathDB
f(x)>1

Source: Iberoamerican Olympiad 1992, Problem 2

May 14, 2007
functionalgebrapolynomialalgebra proposed

Problem Statement

Given the positive real numbers a1<a2<<ana_{1}<a_{2}<\cdots<a_{n}, consider the function f(x)=a1x+a1+a2x+a2++anx+anf(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 disjoint intervals formed by all the values of xx such that f(x)>1f(x)>1.