| changeset 21404 | eb85850d3eb7 |
| parent 20898 | 113c9516a2d7 |
| child 21865 | 55cc354fd2d9 |
--- a/src/HOL/Hyperreal/NthRoot.thy Fri Nov 17 02:19:55 2006 +0100 +++ b/src/HOL/Hyperreal/NthRoot.thy Fri Nov 17 02:20:03 2006 +0100 @@ -11,11 +11,11 @@ begin definition - - root :: "[nat, real] \<Rightarrow> real" + root :: "[nat, real] \<Rightarrow> real" where "root n x = (THE u. (0 < x \<longrightarrow> 0 < u) \<and> (u ^ n = x))" - sqrt :: "real \<Rightarrow> real" +definition + sqrt :: "real \<Rightarrow> real" where "sqrt x = root 2 x"