Question 4
Find all non-constant functions $f : \mathbb{R} \to \mathbb{R}$ that satisfy
$$
f(2xy + x) = f(xy + x) + f(x)f(y)
$$
for all $x, y \in \mathbb{R}$.
$$
f(2xy + x) = f(xy + x) + f(x)f(y)
$$
for all $x, y \in \mathbb{R}$.
MathNet 2023-part-06 — 191 problems (EN–VI) Question 4
Math Olympiad Vault · MathNet 2023-part-06 — 191 problems (EN–VI)