Question 143
Determine all real numbers $A$, $B$ and $C$ such that there exists a real function $f$ that satisfies
$$
f(x+f(y))=A x+B y+C
$$
for all real $x$ and $y$.
$$
f(x+f(y))=A x+B y+C
$$
for all real $x$ and $y$.
MathNet 2008-part-02 — 165 problems (EN–VI) Question 143
Math Olympiad Vault · MathNet 2008-part-02 — 165 problems (EN–VI)