src/HOL/Library/Inner_Product.thy
changeset 51002 496013a6eb38
parent 49962 a8cc904a6820
child 51642 400ec5ae7f8f
--- a/src/HOL/Library/Inner_Product.thy	Thu Jan 31 12:09:07 2013 +0100
+++ b/src/HOL/Library/Inner_Product.thy	Thu Jan 31 17:42:12 2013 +0100
@@ -117,8 +117,6 @@
 subclass real_normed_vector
 proof
   fix a :: real and x y :: 'a
-  show "0 \<le> norm x"
-    unfolding norm_eq_sqrt_inner by simp
   show "norm x = 0 \<longleftrightarrow> x = 0"
     unfolding norm_eq_sqrt_inner by simp
   show "norm (x + y) \<le> norm x + norm y"