Theorem: Fintype.invFun_app (LeanSAT/Upstream/ToMathlib.lean)

State before:
α : Type u_1
α' : Type u_2
inst✝¹ : Fintype α
inst✝ : DecidableEq α'
f : α ↪ α'
f' : α → α'
x : α
h : f' x ∈ Finset.map f Finset.univ
⊢ f' = f.toFun → (invFun f) { val := f' x, property := h } = x
Tactic:
rintro rfl
State after:
α : Type u_1
α' : Type u_2
inst✝¹ : Fintype α
inst✝ : DecidableEq α'
f : α ↪ α'
x : α
h : f.toFun x ∈ Finset.map f Finset.univ
⊢ (invFun f) { val := f.toFun x, property := h } = x

State before:
α : Type u_1
α' : Type u_2
inst✝¹ : Fintype α
inst✝ : DecidableEq α'
f : α ↪ α'
x : α
h : f.toFun x ∈ Finset.map f Finset.univ
⊢ (invFun f) { val := f.toFun x, property := h } = x
Tactic:
simp
State after:
no goals