If $f$ is measured then for every real number a set {$x: f (x) = a$} measured, is the opposite true?

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If $f$ is measured then for every real number a set $\{x: f (x) = a\}$ measured, is the opposite true? favorably we can do the following: for all $a \in R$, $f$ measured $\Longrightarrow \{x:f(x)=a\}=\{x:f(x)\leq a\} \cap\{x:a \leq f(x)\}$ is measured. But if $\{x:f(x)=a\}$ is measured then $f$ measured, is true ???

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No.

Take $V$ to be a non Lebesgue measurable set and $f:V \to \Bbb{R}$ an injective function.

For instance $f(x)=x$