Open_Sets_in_Metric_Space
Provedmetric-spacesopen-setsproofwiki
Let be a metric space. Then and are both open in .
Preamble
import Mathlib.Topology.MetricSpace.Basic
Formal statement
theorem Open_Sets_in_Metric_Space {α : Type _} [MetricSpace α] : IsOpen (Set.univ : Set α) ∧ IsOpen (∅ : Set α) := by sorrySource