diff -r 059c3568fdc8 -r abc6a2ea4b88 src/HOL/Real.thy --- a/src/HOL/Real.thy Fri Apr 02 13:33:48 2010 +0200 +++ b/src/HOL/Real.thy Wed Apr 07 19:17:10 2010 +0200 @@ -2,28 +2,4 @@ imports RComplete RealVector begin -lemma field_le_epsilon: - fixes x y :: "'a:: {number_ring,division_by_zero,ordered_field}" - assumes e: "(!!e. 0 < e ==> x \ y + e)" - shows "x \ y" -proof (rule ccontr) - assume xy: "\ x \ y" - hence "(x-y)/2 > 0" - by (metis half_gt_zero le_iff_diff_le_0 linorder_not_le local.xy) - hence "x \ y + (x - y) / 2" - by (rule e [of "(x-y)/2"]) - also have "... = (x - y + 2*y)/2" - by auto - (metis add_less_cancel_left add_numeral_0_right class_semiring.add_c xy e - diff_add_cancel gt_half_sum less_half_sum linorder_not_le number_of_Pls) - also have "... = (x + y) / 2" - by auto - also have "... < x" using xy - by auto - finally have "x