X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fmatita%2Flibrary%2Fnat%2Fminus.ma;h=710418d72644022cb4d799fb95f67354da4af89b;hb=4167cea65ca58897d1a3dbb81ff95de5074700cc;hp=00a90acd83192ee2d79d6b8b59c7a1e37d2e21ff;hpb=b3f74fab711510628cff64aff3e48e73cc9f6e09;p=helm.git diff --git a/helm/matita/library/nat/minus.ma b/helm/matita/library/nat/minus.ma index 00a90acd8..710418d72 100644 --- a/helm/matita/library/nat/minus.ma +++ b/helm/matita/library/nat/minus.ma @@ -170,7 +170,7 @@ qed. theorem lt_minus_m: \forall n,m:nat. O < n \to O < m \to n-m \lt n. intros.apply (lt_O_n_elim n H).intro. apply (lt_O_n_elim m H1).intro. -simplify.apply le_S_S.apply le_minus_m. +simplify.unfold lt.apply le_S_S.apply le_minus_m. qed. theorem minus_le_O_to_le: \forall n,m:nat. n-m \leq O \to n \leq m. @@ -230,14 +230,14 @@ theorem lt_minus_to_plus: \forall n,m,p. (lt n (p-m)) \to (lt (n+m) p). intros 3.apply (nat_elim2 (\lambda m,p.(lt n (p-m)) \to (lt (n+m) p))). intro.rewrite < plus_n_O.rewrite < minus_n_O.intro.assumption. simplify.intros.apply False_ind.apply (not_le_Sn_O n H). -simplify.intros. +simplify.intros.unfold lt. apply le_S_S. rewrite < plus_n_Sm. apply H.apply H1. qed. theorem distributive_times_minus: distributive nat times minus. -simplify. +unfold distributive. intros. apply ((leb_elim z y)). intro.cut (x*(y-z)+x*z = (x*y-x*z)+x*z).