∀ {𝕜 : Type u_1} [inst : NontriviallyNormedField 𝕜] {E : Type uE} [inst_1 : NormedAddCommGroup E]
  [inst_2 : NormedSpace 𝕜 E] {s : Set E} {𝕜' : Type u_6} [inst_3 : NormedField 𝕜'] [inst_4 : NormedAlgebra 𝕜 𝕜']
  {f : E → 𝕜'} {n : WithTop ℕ∞}, ContDiffOn 𝕜 n f s → ∀ (c : 𝕜'), ContDiffOn 𝕜 n (fun x => f x / c) s