Closed set: Difference between revisions

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imported>Hendra I. Nurdin
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A set <math>A \subset X</math>, where <math>(X,O)</math> is some [[topological space]], is said to be closed if <math>X-A=\{x \in X \mid x \notin A\}</math>, the complement of <math>A</math> in <math>X</math>, is an [[open set]]
In [[mathematics]], a set <math>A \subset X</math>, where <math>(X,O)</math> is some [[topological space]], is said to be closed if <math>X-A=\{x \in X \mid x \notin A\}</math>, the complement of <math>A</math> in <math>X</math>, is an [[open set]]


== See also ==
== See also ==
[[Topology]]
[[Analysis]]
[[Analysis]]


[[Category:Mathematics Workgroup]]
[[Category:Mathematics Workgroup]]

Revision as of 08:13, 31 August 2007

In mathematics, a set , where is some topological space, is said to be closed if , the complement of in , is an open set

See also

Topology

Analysis