rw [Subgraph.mem_edgeSet] at he
case h
α : Type u_1
β : Type u_2
γ : Type u_3
V : Type u_4
G H : SimpleGraph V
G' : G.Subgraph
a b : V
he : s(a, b) ∈ G'.edgeSet
⊢ s(a, b) ∈ Set.range (Sym2.map Subtype.val)
case h
α : Type u_1
β : Type u_2
γ : Type u_3
V : Type u_4
G H : SimpleGraph V
G' : G.Subgraph
a b : V
he : G'.Adj a b
⊢ s(a, b) ∈ Set.range (Sym2.map Subtype.val)