2011 IMO Problems/Problem 3
Revision as of 17:20, 20 July 2011 by Humzaiqbal (talk | contribs) (Created page with "Let f : R → R be a real-valued function defined on the set of real numbers that satisfies f(x + y) ≤ yf(x) + f(f(x)) for all real numbers x and y. Prove that f(x) = 0 for all...")
Let f : R → R be a real-valued function defined on the set of real numbers that satisfies f(x + y) ≤ yf(x) + f(f(x)) for all real numbers x and y. Prove that f(x) = 0 for all x≤ 0.
