Closure (Topology)/Examples/Open Interval in Open Unbounded Interval

Example of Closure in the context of Topology

Let $S$ be the open real interval:

$S = \openint a \to$

Let $H$ be the open real interval:

$H = \openint a b$

Then the closure of $H$ in $S$ is:

$H^- = \hointl a b$

Sources

• 1975: W.A. Sutherland: Introduction to Metric and Topological Spaces ... (previous) ... (next): $3$: Continuity generalized: topological spaces: $3.7$: Definitions: Examples $3.7.14 \ \text {(a)}$