Theorems · Theorem · general topology

isOpen_ne_fun

∀ {X : Type u_1} {Y : Type u_2} [inst : TopologicalSpace X] [inst_1 : TopologicalSpace Y] [T2Space X] {f g : Y → X},
  Continuous f → Continuous g → IsOpen {y | f y ≠ g y}

Defined in

Mathlib.Topology.Separation.Hausdorff

Cited by

1 results in Mathlib

Foundations

Depth 74 from the axioms · uses propext, Classical.choice, Quot.sound

Assumes

TopologicalSpaceTopologicalSpaceT2Space