Image of an Open Set Under Continuous Function

The Image of an Open Set Under Continuous Function

Remark

Remark. Let $(X,{\tau }_X)$ and $(Y,{\tau }_Y)$ be topological spaces. The image of an open (resp. closed) set of a continuous function $f:X\to Y$ is not necessarily open (resp. closed) in $Y$.

References

@Bou95 pp. 27 Slipery note