MathDB
f^(n+1)(x)>f^(n)(x)+c, f analytic

Source: VJIMC 2008 1.3

June 16, 2021
differential equationcalculus

Problem Statement

Find all cRc\in\mathbb R for which there exists an infinitely differentiable function f:RRf:\mathbb R\to\mathbb R such that for all nNn\in\mathbb N and xRx\in\mathbb R we have f(n+1)(x)>f(n)(x)+c.f^{(n+1)}(x)>f^{(n)}(x)+c.