MathDB
f(x) f(k - x) > 0

Source: 2001 Cuba MO 2.1

September 15, 2024
inequalitiesalgebra

Problem Statement

Let ff be a linear function such that f(0)=5f(0) = -5 and f(f(0))=15f(f(0)) = -15. Find the values of kR k \in R for which the solutions of the inequality f(x)f(kx)>0f(x) \cdot f(k - x) > 0, lie in an interval of length 22.