Cover

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Definition

An arbitrary family of sets, [ilmath]\{S_\alpha\}_{\alpha\in I}[/ilmath] is said to cover another set, [ilmath]X[/ilmath] if[1]:

  • [math]X\subseteq\bigcup_{\alpha\in I}S_\alpha[/math], that is to say that:
  • [ilmath]X[/ilmath] is contained in the union of the members of the family.

See also

References

  1. Introduction to Topology - Theodore W. Gamelin & Robert Everist Greene