English
The inverse of a bijective morphism is a morphism.
Русский
Обратный картограф bijective гомоморфизм является гомоморфизмом.
LaTeX
$$$\text{If } f: A \to B \text{ is bijective, then } f^{-1}: B \to A \text{ is a morphism.}$$$
Lean4
/-- The inverse of a bijective morphism is a morphism. -/
def inverse (f : A →ₙₐ[R] B₁) (g : B₁ → A) (h₁ : Function.LeftInverse g f) (h₂ : Function.RightInverse g f) :
B₁ →ₙₐ[R] A :=
{ (f : A →ₙ* B₁).inverse g h₁ h₂, (f : A →+[R] B₁).inverse g h₁ h₂ with }