no goals
F : Type ?u.2807
ι : Type ?u.2810
α : Type u_1
β : Type ?u.2816
inst✝ : DivisionRing α
r : ℚ
a : α
⊢ Commute (↑r) a
simpa only [cast_def] using (r.1.cast_commute a).div_left (r.2.cast_commute a)