induction as <;> simp
α : Type u_1
β : Type u_2
r : α → β → Prop
as : List α
bs : List β
⊢ List.forAllRel (flip r) bs as = List.forAllRel r as bs
case cons
α : Type u_1
β : Type u_2
r : α → β → Prop
bs : List β
head✝ : α
tail✝ : List α
tail_ih✝ : List.forAllRel (flip r) bs tail✝ = List.forAllRel r tail✝ bs
⊢ forAll (fun x => flip r x head✝) bs ∧ List.forAllRel (flip r) bs tail✝ ↔
    forAll (r head✝) bs ∧ List.forAllRel r tail✝ bs