∀ {R₁ : Type u_3} [inst : CommRing R₁] {K : Type u_4} [inst_1 : Field K] [inst_2 : Algebra R₁ K]
  [inst_3 : IsFractionRing R₁ K] [inst_4 : IsDomain R₁] {K' : Type u_5} [inst_5 : Field K'] [inst_6 : Algebra R₁ K']
  [inst_7 : IsFractionRing R₁ K'] (I : FractionalIdeal (nonZeroDivisors R₁) K) (h : K ≃ₐ[R₁] K'),
  FractionalIdeal.map (↑h) (1 / I) = 1 / FractionalIdeal.map (↑h) I