Question 87
Find all functions $f : \mathbb{R} \to \mathbb{R}$ satisfying
$$
f(x + y) \leq f(x^2 + y),
$$
for all $x, y \in \mathbb{R}$.
$$
f(x + y) \leq f(x^2 + y),
$$
for all $x, y \in \mathbb{R}$.
MathNet 2019-part-05 — 184 problems (EN–VI) Question 87
Math Olympiad Vault · MathNet 2019-part-05 — 184 problems (EN–VI)