Question 6
Give an example of a strictly increasing function $f: \mathbb{R} \rightarrow [0,1]$ with the property that
$$
f(x+y) \leq f(x)+f(y)
$$
for any real numbers $x$ and $y$.
$$
f(x+y) \leq f(x)+f(y)
$$
for any real numbers $x$ and $y$.
MathNet 2018-part-07 — 177 problems (EN–VI) Question 6
Math Olympiad Vault · MathNet 2018-part-07 — 177 problems (EN–VI)