X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Flibrary%2Fnat%2Fdiv_and_mod.ma;h=2f186dd31ae1ff0cf31eb5971c59c388d14ba349;hb=c9806f330ca060719dc21440b1b6d0dfe596f01f;hp=e9831f82ad1ec5cc01decf9e920f9e80518c3f64;hpb=7f2444c2670cadafddd8785b687ef312158376b0;p=helm.git

diff --git a/matita/library/nat/div_and_mod.ma b/matita/library/nat/div_and_mod.ma
index e9831f82a..2f186dd31 100644
--- a/matita/library/nat/div_and_mod.ma
+++ b/matita/library/nat/div_and_mod.ma
@@ -266,7 +266,7 @@ variant inj_times_r : \forall n,p,q:nat.(S n)*p = (S n)*q \to p=q \def
 injective_times_r.
 
 theorem lt_O_to_injective_times_r: \forall n:nat. O < n \to injective nat nat (\lambda m:nat.n*m).
-change with (\forall n. O < n \to \forall p,q:nat.n*p = n*q \to p=q).
+simplify.
 intros 4.
 apply (lt_O_n_elim n H).intros.
 apply (inj_times_r m).assumption.
@@ -276,11 +276,11 @@ variant inj_times_r1:\forall n. O < n \to \forall p,q:nat.n*p = n*q \to p=q
 \def lt_O_to_injective_times_r.
 
 theorem injective_times_l: \forall n:nat.injective nat nat (\lambda m:nat.m*(S n)).
-change with (\forall n,p,q:nat.p*(S n) = q*(S n) \to p=q).
+simplify.
 intros.
-apply (inj_times_r n p q).
+apply (inj_times_r n x y).
 rewrite < sym_times.
-rewrite < (sym_times q).
+rewrite < (sym_times y).
 assumption.
 qed.
 
@@ -288,7 +288,7 @@ variant inj_times_l : \forall n,p,q:nat. p*(S n) = q*(S n) \to p=q \def
 injective_times_l.
 
 theorem lt_O_to_injective_times_l: \forall n:nat. O < n \to injective nat nat (\lambda m:nat.m*n).
-change with (\forall n. O < n \to \forall p,q:nat.p*n = q*n \to p=q).
+simplify.
 intros 4.
 apply (lt_O_n_elim n H).intros.
 apply (inj_times_l m).assumption.