no goals
α : Type u_1
β : Type ?u.320195
γ : Type ?u.320198
p q : α → Prop
inst✝¹ : DecidablePred p
inst✝ : DecidablePred q
s : Finset α
a : α
⊢ a ∈ filter q (filter p s) ↔ a ∈ filter (fun a => p a ∧ q a) s
simp only [mem_filter, and_assoc, Bool.decide_and, Bool.decide_coe, Bool.and_eq_true]