Question 73
Find all functions $f: \mathbb{R} \rightarrow \mathbb{R}$ that satisfy
$$
f\left(x+y^{2}-f(y)\right)=f(x)
$$
for all $x, y \in \mathbb{R}$.
$$
f\left(x+y^{2}-f(y)\right)=f(x)
$$
for all $x, y \in \mathbb{R}$.
MathNet 2015-part-05 — 191 problems (EN–VI) Question 73
Math Olympiad Vault · MathNet 2015-part-05 — 191 problems (EN–VI)