intros a b; case a; case b; simpl in |- *; auto.
intros a0 m a1 m0 H.
apply A_sep with (2 := eqA_dec) (1 := cs); auto.
Qed.

Theorem multTerm_minusTerm_dist_l :
forall a b c : Term,
eqT a b ->
eqTerm (minusTerm (multTerm a c) (multTerm b c))
(multTerm (minusTerm a b) c).