aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--theories/Reals/Rbasic_fun.v5
1 files changed, 2 insertions, 3 deletions
diff --git a/theories/Reals/Rbasic_fun.v b/theories/Reals/Rbasic_fun.v
index fb164fde6e..c586acdca0 100644
--- a/theories/Reals/Rbasic_fun.v
+++ b/theories/Reals/Rbasic_fun.v
@@ -410,11 +410,10 @@ Qed.
(* ||a|-|b||<=|a-b| *)
Lemma Rabsolu_triang_inv2 : (a,b:R) ``(Rabsolu ((Rabsolu a)-(Rabsolu b)))<=(Rabsolu (a-b))``.
Cut (a,b:R) ``(Rabsolu b)<=(Rabsolu a)``->``(Rabsolu ((Rabsolu a)-(Rabsolu b))) <= (Rabsolu (a-b))``.
-Intros; Case (total_order_T (Rabsolu a) (Rabsolu b)); Intro.
-Elim s; Intro.
+Intros; NewDestruct (total_order (Rabsolu a) (Rabsolu b)) as [Hlt|[Heq|Hgt]].
Rewrite <- (Rabsolu_Ropp ``(Rabsolu a)-(Rabsolu b)``); Rewrite <- (Rabsolu_Ropp ``a-b``); Do 2 Rewrite Ropp_distr2.
Apply H; Left; Assumption.
-Rewrite b0; Unfold Rminus; Rewrite Rplus_Ropp_r; Rewrite Rabsolu_R0; Apply Rabsolu_pos.
+Rewrite Heq; Unfold Rminus; Rewrite Rplus_Ropp_r; Rewrite Rabsolu_R0; Apply Rabsolu_pos.
Apply H; Left; Assumption.
Intros; Replace ``(Rabsolu ((Rabsolu a)-(Rabsolu b)))`` with ``(Rabsolu a)-(Rabsolu b)``.
Apply Rabsolu_triang_inv.