# HG changeset patch # User huffman # Date 1156365872 -7200 # Node ID eba80f91e3fccf0742aee1acc5155dfe9949ce54 # Parent f6ccfc09694a116781da12c65cc4df3f786d5a0b speed up some proofs diff -r f6ccfc09694a -r eba80f91e3fc src/HOL/Hyperreal/Lim.thy --- a/src/HOL/Hyperreal/Lim.thy Wed Aug 23 22:12:54 2006 +0200 +++ b/src/HOL/Hyperreal/Lim.thy Wed Aug 23 22:44:32 2006 +0200 @@ -93,9 +93,9 @@ lemma LIM_add: assumes f: "f -- a --> L" and g: "g -- a --> M" shows "(%x. f x + g(x)) -- a --> (L + M)" -proof (simp add: LIM_eq, clarify) +proof (unfold LIM_eq, clarify) fix r :: real - assume r: "0 a \ \x-a\ < min fs gs" + hence "x \ a \ \x-a\ < fs \ \x-a\ < gs" by simp with fs_lt gs_lt - have "\f x - L\ < r/2" and "\g x - M\ < r/2" by (auto simp add: fs_lt) + have "\f x - L\ < r/2" and "\g x - M\ < r/2" by blast+ hence "\f x - L\ + \g x - M\ < r" by arith thus "\f x + g x - (L + M)\ < r" by (blast intro: abs_diff_triangle_ineq order_le_less_trans) @@ -194,8 +195,9 @@ show "0 < min fs gs" by (simp add: fs gs) fix x :: real assume "x \ a \ \x-a\ < min fs gs" + hence "x \ a \ \x-a\ < fs \ \x-a\ < gs" by simp with fs_lt gs_lt - have "\f x\ < 1" and "\g x\ < r" by (auto simp add: fs_lt) + have "\f x\ < 1" and "\g x\ < r" by blast+ hence "\f x\ * \g x\ < 1*r" by (rule abs_mult_less) thus "\f x\ * \g x\ < r" by simp qed