Question 92
Find all functions $f : \mathbb{R} \to \mathbb{R}$, satisfying the identity
$$
f(x^2 + xy + f(y)) = (f(x))^2 + x f(y) + y
$$
for all $x, y \in \mathbb{R}$.
$$
f(x^2 + xy + f(y)) = (f(x))^2 + x f(y) + y
$$
for all $x, y \in \mathbb{R}$.
MathNet 2006 — Part 04 Question 92
Math Olympiad Vault · MathNet 2006 — Part 04