VN-TST 2007 Problem 4

Find all continuous functions $f: \mathbb{R}\to\mathbb{R}$ such that for all real $x$ we have $f(x)=f\left(x^{2}+\frac{x}{3}+\frac{1}{9}\right).$

Dataset text AI-MO AoPS. Quoted with source.

Solutions

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