Corollary

Tag 0C8T, permanent. Cite it as [Bourbaki, Tag 0C8T].

General Topology, chapter IX, § 6. Polish spaces, Souslin spaces, Borel sets

Let $f$ be a continuous mapping of a Souslin space $X$ into a metrizable space $Y$ . If $B$ is any Borel set in $X$ , then $f(B)$ is a Souslin set in $Y$ .

For $B$ is a Souslin space, hence so is $f(B)$ by the remark following Definition 2 (no. 2).

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

Definition 2