It's obviously not injective in the case of $f(x)=0$. I'm wondering if it's injective in all other cases. The other linear solutions of the form $f(x)=c\cdot x$ where $c$ is some constant are injective, what about the "wild" additive functions?
2026-04-05 17:16:49.1775409409
Is the function from the Cauchy functional equation, $f(x+y)=f(x)+f(y)$ injective?
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