Question 17
Find all functions $f: \mathbb{R} \to \mathbb{R}$, such that
$$
f(xy) = x f(y) + 3 f(x) + 3
$$
for all $x, y \in \mathbb{R}$.
$$
f(xy) = x f(y) + 3 f(x) + 3
$$
for all $x, y \in \mathbb{R}$.
MathNet 2014 Question 17
Math Olympiad Vault · MathNet 2014