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

State before:
α : Type u_1
α' : Type u_2
inst✝¹ : Fintype α
inst✝ : DecidableEq α'
f : α ↪ α'
x : { x // x ∈ Finset.map f Finset.univ }
y : α
⊢ (invFun f) x = y ↔ ↑x = f y
Tactic:
simp [invFun]
State after:
no goals