{A : Ring} (x y z : A) : x * (y - z) = x * y - x * z. Proof. lhs nrapply rng_dist_l. nrapply ap. nrapply rng_mult_negate_r. Defined.
Require Import WildCat. Require Import Spaces.Nat.Core Spaces.Nat.Arithmetic. Require Import Classes.interfaces.abstract_algebra. Require Import Algebra.Groups.Group Algebra.Groups.Subgroup. Require Import Modalities.ReflectiveSubuniverse.