MathDB
Determine continuous functions

Source: RMO 2004, Grade 12, Problem 1

February 26, 2006
functionintegrationcalculusderivativelimitalgebrafunctional equation

Problem Statement

Find all continuous functions f:RRf : \mathbb R \to \mathbb R such that for all xRx \in \mathbb R and for all nNn \in \mathbb N^{\ast} we have n2xx+1nf(t)dt=nf(x)+12. n^2 \int_{x}^{x + \frac{1}{n}} f(t) \, dt = n f(x) + \frac12 . Mihai Piticari