Open subset of open subspace is open: Difference between revisions

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(Created page with "==Statement== Suppose <math>X</math> is a topological space and <math>V</math> is an open subset of <math>X</math>. Suppose <math>U</math> is a subset of <math>V</mat...")
 
 
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* [[Closed subset of closed subspace is closed]]
* [[Closed subset of closed subspace is closed]]
* [[Dense subset of dense subspace is dense]]

Latest revision as of 01:01, 25 January 2012

Statement

Suppose X is a topological space and V is an open subset of X. Suppose U is a subset of V that is an open subset of V under the subspace topology on V. Then, U is also an open subset of X.

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