//N bug, but WHY?

*To*: mathgroup at smc.vnet.net*Subject*: [mg58634] //N bug, but WHY?*From*: "symbio" <symbio at has.com>*Date*: Mon, 11 Jul 2005 04:19:20 -0400 (EDT)*Reply-to*: "symbio" <symbio at sha.com>*Sender*: owner-wri-mathgroup at wolfram.com

Evaluating (using //N) two exact same expressions, gives wrong answer unless fullsimplify is used first, I spent 2 days on a problem thinking my answer was wrong, but turned out Mathematica 5 was giving me buggy answers, I debugged it to this point, but WHY in the world is this happening? Please help!!! cut and paste below to see the test case: In[243]:= \!\(\(Cosh[\(43\ \[Pi]\)\/\@2] + \((1 - Cosh[43\ \@2\ \[Pi]])\)\ Csch[ 43\ \@2\ \[Pi]]\ Sinh[\(43\ \[Pi]\)\/\@2] // FullSimplify\) // N\[IndentingNewLine] Cosh[\(43\ \[Pi]\)\/\@2] + \((1 - Cosh[43\ \@2\ \[Pi]])\)\ Csch[ 43\ \@2\ \[Pi]]\ Sinh[\(43\ \[Pi]\)\/\@2] // N\) Out[243]= \!\(6.551787517854307`*^-42\) Out[244]= \!\(\(-1.9342813113834067`*^25\)\) thanks,

**Follow-Ups**:**Re: //N bug, but WHY?***From:*Andrzej Kozlowski <akozlowski@gmail.com>