intros a b nZb H; inversion H; auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with (y := multTerm (A:=A) multA (n:=n) (divTerm a nZb0) b);
auto.
Qed.
Hint Resolve divP_inv1 divP_inv2 divP_inv3.

Theorem divP_plusTerm :
forall a b c : Term A n,
divP a c ->
divP b c ->
eqT a b ->
~ zeroP (A:=A) A0 eqA (n:=n) (plusTerm (A:=A) plusA (n:=n) a b) ->
divP (plusTerm (A:=A) plusA (n:=n) a b) c.