MathDB
IMC 2009 Day 2 P2

Source:

July 16, 2014
functioninequalitiesIMCcollege contestsIntegral inequality

Problem Statement

Suppose f:RRf:\mathbb{R}\to \mathbb{R} is a two times differentiable function satisfying f(0)=1,f(0)=0f(0)=1,f^{\prime}(0)=0 and for all x[0,)x\in [0,\infty), it satisfies f(x)5f(x)+6f(x)0 f^{\prime \prime}(x)-5f^{\prime}(x)+6f(x)\ge 0 Prove that, for all x[0,)x\in [0,\infty), f(x)3e2x2e3x f(x)\ge 3e^{2x}-2e^{3x}