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Une fonction $f : [0,1] \to \mathbb{R}$ est continue si

\[
	\forall x \in [0,1], \forall \varepsilon > 0, \exists \delta > 0, \forall y \in [0,1] : \vert y - x \vert < \delta \implies \vert f(y) - f(x) \vert < \varepsilon
\]

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