Question 59
Determine all functions $f : \mathbb{R} \to \mathbb{R}$ which satisfy the inequality $f(x) + f(x+y) \le f(xy) + f(y)$ for all real numbers $x, y$.
MathNet 2022-part-02 — 197 problems (EN–VI) Question 59
Math Olympiad Vault · MathNet 2022-part-02 — 197 problems (EN–VI)