intros a b; case a; case b; simpl in |- *.
unfold red in |- *; simpl in |- *.
intros x Cx x0 Cx0 aL H'1; inversion H'1.
cut
(canonical A0 eqA ltM
(spolyf A A0 A1 eqA invA minusA multA divA eqA_dec n ltM ltM_dec x x0 Cx
Cx0)); [ intros Op1 | apply spolyf_canonical with (1 := cs) ];
auto.
cut
(canonical A0 eqA ltM
(spolyf A A0 A1 eqA invA minusA multA divA eqA_dec n ltM ltM_dec x0 x Cx0
Cx)); [ intros Op2 | apply spolyf_canonical with (1 := cs) ];
auto.
apply reducestar0; auto.
apply
reduceplus_eqp_com
with
(1 := cs)
(p := mults (A:=A) multA (n:=n) (invTerm (A:=A) invA (n:=n) (T1 A1 n))
(spolyf A A0 A1 eqA invA minusA multA divA eqA_dec n ltM ltM_dec
x x0 Cx Cx0))
(q := mults (A:=A) multA (n:=n) (invTerm (A:=A) invA (n:=n) (T1 A1 n))
(pO A n)); auto.
apply reduceplus_mults with (1 := cs); auto.
inversion H; auto.
apply (eqp_sym _ _ _ _ _ _ _ _ _ cs n); auto.
apply spolyf_com with (1 := cs); auto.
apply (eqp_sym _ _ _ _ _ _ _ _ _ cs n); auto.
apply spolyf_com with (1 := cs); auto.
Qed.

Theorem rstar_rtopO :
forall (Q : list (poly A0 eqA ltM)) (p : list (Term A n)),
canonical A0 eqA ltM p ->
reduceplus A A0 A1 eqA invA minusA multA divA eqA_dec n ltM ltM_dec Q p
(pO A n) ->
reducestar A A0 A1 eqA invA minusA multA divA eqA_dec n ltM ltM_dec Q p
(pO A n).