# An algebra problem by Manuel Kahayon

Algebra Level 2

Does there exist a function $f: \mathbb{R} \to \mathbb{R}$ which satisfies

1. $f(x)$ is bijective;
2. $f(x)$ is neither non-increasing nor non-decreasing;
3. $f\big(f(x)\big)$ is non-decreasing?
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