# Function(function)

Algebra Level 2

Let $$f(x)$$ be defined on $$[0,1]$$ by the rule $f(x)=\begin{cases}x & \mbox{if }x\in\mathbb{Q} \\ 1-x & \mbox{if }x\notin\mathbb{Q}\end{cases}$ Then for all $$x\in[0,1]$$, $$f(f(x))$$ is

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