exact fun h ↦ ⟨_, by rw [← h]; exact smul_mem_smul_finset hb, _, hb, mul_div_cancel_right _ _⟩
case intro
ι : Type u_1
α : Type u_2
inst✝¹ : Group α
inst✝ : DecidableEq α
s t : Finset α
a b : α
hb : b ∈ s
⊢ a • s = s → ∃ b ∈ s, ∃ c ∈ s, b / c = a
no goals