Find all functions $f : R \to R$ that satisfy $f(x + y^2 - f(y)) = f(x)$ for all $x,y \in R$. (Vo Quoc Ba Can)
Source: 2015 Saudi Arabia Pre-TST 2.2
Tags: algebra, functional
Find all functions $f : R \to R$ that satisfy $f(x + y^2 - f(y)) = f(x)$ for all $x,y \in R$. (Vo Quoc Ba Can)