no goals
ι : Type ?u.93506
α : Type u_1
inst✝² : PartialOrder α
inst✝¹ : LocallyFiniteOrder α
a b c : α
inst✝ : DecidableEq α
h : a ≤ b
⊢ insert a (Ioc a b) = Icc a b
rw [← coe_inj, coe_insert, coe_Ioc, coe_Icc, Set.insert_eq, Set.union_comm, Set.Ioc_union_left h]