MathGroup Archive 2003

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Simplification of radicals

  • To: mathgroup at smc.vnet.net
  • Subject: [mg43310] Re: [mg43243] Simplification of radicals
  • From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
  • Date: Sun, 24 Aug 2003 04:55:07 -0400 (EDT)
  • Sender: owner-wri-mathgroup at wolfram.com

Note:

In[17]:=
Simplify[Sqrt[1/x^2]*Sqrt[x^2], x $B":(B Reals]

Out[17]=
1

Now observe that

In[18]:=
Sqrt[1/x^2]*Sqrt[x^2] /. x -> I

Out[18]=
-1



Andrzej Kozlowski
Yokohama, Japan
http://www.mimuw.edu.pl/~akoz/
http://platon.c.u-tokyo.ac.jp/andrzej/

On Saturday, August 23, 2003, at 02:08 PM, Alex wrote:

> I tried this simple example
>
> (************** Content-type: application/mathematica **************
>                      CreatedBy='Mathematica 4.2'
>
>                     Mathematica-Compatible Notebook
>
> This notebook can be used with any Mathematica-compatible
> application, such as Mathematica, MathReader or Publicon. The data
> for the notebook starts with the line containing stars above.
>
> To get the notebook into a Mathematica-compatible application, do
> one of the following:
>
> * Save the data starting with the line of stars above into a file
>   with a name ending in .nb, then open the file inside the
>   application;
>
> * Copy the data starting with the line of stars above to the
>   clipboard, then use the Paste menu command inside the application.
>
> Data for notebooks contains only printable 7-bit ASCII and can be
> sent directly in email or through ftp in text mode.  Newlines can be
> CR, LF or CRLF (Unix, Macintosh or MS-DOS style).
>
> NOTE: If you modify the data for this notebook not in a Mathematica-
> compatible application, you must delete the line below containing
> the word CacheID, otherwise Mathematica-compatible applications may
> try to use invalid cache data.
>
> For more information on notebooks and Mathematica-compatible
> applications, contact Wolfram Research:
>   web: http://www.wolfram.com
>   email: info at wolfram.com
>   phone: +1-217-398-0700 (U.S.)
>
> Notebook reader applications are available free of charge from
> Wolfram Research.
> *******************************************************************)
>
> (*CacheID: 232*)
>
>
> (*NotebookFileLineBreakTest
> NotebookFileLineBreakTest*)
> (*NotebookOptionsPosition[      1917,         60]*)
> (*NotebookOutlinePosition[      2559,         82]*)
> (*  CellTagsIndexPosition[      2515,         78]*)
> (*WindowFrame->Normal*)
>
>
>
> Notebook[{
>
> Cell[CellGroupData[{
> Cell[BoxData[
>     \(Simplify[\(\@\(1\/x\^2\)\) \@x\^2]\)], "Input"],
>
> Cell[BoxData[
>     \(\@\(1\/x\^2\)\ \@x\^2\)], "Output"]
> }, Open  ]]
> },
> FrontEndVersion->"4.2 for Microsoft Windows",
> ScreenRectangle->{{0, 720}, {0, 407}},
> WindowSize->{496, 249},
> WindowMargins->{{0, Automatic}, {Automatic, 0}}
> ]
>
> (*******************************************************************
> Cached data follows.  If you edit this Notebook file directly, not
> using Mathematica, you must remove the line containing CacheID at
> the top of  the file.  The cache data will then be recreated when
> you save this file from within Mathematica.
> *******************************************************************)
>
> (*CellTagsOutline
> CellTagsIndex->{}
> *)
>
> (*CellTagsIndex
> CellTagsIndex->{}
> *)
>
> (*NotebookFileOutline
> Notebook[{
>
> Cell[CellGroupData[{
> Cell[1776, 53, 67, 1, 51, "Input"],
> Cell[1846, 56, 55, 1, 51, "Output"]
> }, Open  ]]
> }
> ]
> *)
>
>
>
> (*******************************************************************
> End of Mathematica Notebook file.
> *******************************************************************)
>
>
> How come Mathematica couldn't simplify such a elementary thing?
>
> Alex
>
>
>



  • Prev by Date: Re: Simplification of radicals
  • Next by Date: Re: Re: Re: New version, new bugs
  • Previous by thread: Re: Simplification of radicals
  • Next by thread: elliptic equation solved with 2 boundaries