∀ {H : Type x} [inst : TopologicalSpace H] [inst_1 : CommGroup H] [inst_2 : PartialOrder H] [IsOrderedMonoid H]
  [ContinuousMul H] {c a : H},
  Filter.map (fun x => x * c) (nhdsWithin a (Set.Iio a)) = nhdsWithin (a * c) (Set.Iio (a * c))