MathDB
$g(x) = f(x) f(1-x)$

Source: 41-st Vietnamese Mathematical Olympiad 2003

March 10, 2007
functiontrigonometrycalculusalgebra proposedalgebra

Problem Statement

Let f:RRf: \mathbb{R}\to\mathbb{R} is a function such that f(cotx)=cos2x+sin2xf( \cot x ) = \cos 2x+\sin 2x for all 0<x<π0 < x < \pi. Define g(x)=f(x)f(1x)g(x) = f(x) f(1-x) for 1x1-1 \leq x \leq 1. Find the maximum and minimum values of gg on the closed interval [1,1].[-1, 1].