Question 58
Find all functions $f: \mathbb{R} \rightarrow \mathbb{R}$ such that
$$
f(f(x) f(y)+y)=f(x) y+f(y-x+1)
$$
for all $x, y \in \mathbb{R}$.
$$
f(f(x) f(y)+y)=f(x) y+f(y-x+1)
$$
for all $x, y \in \mathbb{R}$.
MathNet 2026 — Part 07 Question 58
Math Olympiad Vault · MathNet 2026 — Part 07