# HG changeset patch # User wenzelm # Date 1015435008 -3600 # Node ID d3be9be2b307f84b34e3f0774b86c46d4bfc08f0 # Parent d7bb6e4f5f8281448690ef4928d59c6b6aaba590 tuned; diff -r d7bb6e4f5f82 -r d3be9be2b307 src/HOL/Hyperreal/ex/Sqrt.thy --- a/src/HOL/Hyperreal/ex/Sqrt.thy Wed Mar 06 17:56:02 2002 +0100 +++ b/src/HOL/Hyperreal/ex/Sqrt.thy Wed Mar 06 18:16:48 2002 +0100 @@ -23,7 +23,8 @@ \m n. n \ 0 \ \x\ = real m / real n \ gcd (m, n) = 1" proof - assume "x \ \" - then obtain m n :: nat where n: "n \ 0" and x_rat: "\x\ = real m / real n" + then obtain m n :: nat where + n: "n \ 0" and x_rat: "\x\ = real m / real n" by (unfold rationals_def) blast let ?gcd = "gcd (m, n)" from n have gcd: "?gcd \ 0" by (simp add: gcd_zero) @@ -40,7 +41,8 @@ moreover have "\x\ = real ?k / real ?l" proof - - from gcd have "real ?k / real ?l = real (?gcd * ?k) / real (?gcd * ?l)" + from gcd have "real ?k / real ?l = + real (?gcd * ?k) / real (?gcd * ?l)" by (simp add: real_mult_div_cancel1) also from gcd_k and gcd_l have "\ = real m / real n" by simp also from x_rat have "\ = \x\" .. @@ -103,12 +105,6 @@ with p show False by simp qed -text {* - Just for the record: we instantiate the main theorem for the - specific prime number @{text 2} (real mathematicians would never do - this formally :-). -*} - corollary "sqrt (real (2::nat)) \ \" by (rule sqrt_prime_irrational) (rule two_is_prime) diff -r d7bb6e4f5f82 -r d3be9be2b307 src/HOL/Hyperreal/ex/Sqrt_Script.thy --- a/src/HOL/Hyperreal/ex/Sqrt_Script.thy Wed Mar 06 17:56:02 2002 +0100 +++ b/src/HOL/Hyperreal/ex/Sqrt_Script.thy Wed Mar 06 18:16:48 2002 +0100 @@ -23,8 +23,8 @@ apply (rule_tac j = "k * k" in dvd_mult_left, simp) done -lemma reduction: - "p \ prime \ 0 < k \ k * k = p * (j * j) \ k < p * j \ 0 < j" +lemma reduction: "p \ prime \ + 0 < k \ k * k = p * (j * j) \ k < p * j \ 0 < j" apply (rule ccontr) apply (simp add: linorder_not_less) apply (erule disjE)