no goals
α : Type u_1
inst✝¹ : LinearOrder α
inst✝ : LocallyFiniteOrder α
a✝ b✝ c✝ d a b c : α
⊢ filter (fun x => c ≤ x) (Ico a b) = Ico (max a c) b
rw [Ico, Ico, ← Finset.filter_val, Finset.Ico_filter_le]