∀ {α : Type u_1} {β : Type u_2} [inst : Field α] [inst_1 : LinearOrder α] [inst_2 : IsStrictOrderedRing α]
  [inst_3 : Ring β] {abv : β → α} [inst_4 : IsAbsoluteValue abv] (g : CauSeq β abv) {f : CauSeq β abv},
  f ≈ 0 → f * g ≈ 0