       Re: A Series test

• To: mathgroup at smc.vnet.net
• Subject: [mg72784] Re: A Series test
• From: "Scout" <sarner2006-sem at yahoo.it>
• Date: Fri, 19 Jan 2007 02:05:37 -0500 (EST)
• References: <eonhr6\$i8\$1@smc.vnet.net>

```If you want to try another way to solve your problem,
This package also needs the file "NonNegativeQ.m"
http://library.wolfram.com/infocenter/MathSource/647/

HTH,
~Scout~

news:eonhr6\$i8\$1 at smc.vnet.net...
> Just curious. Could somebody pls run this script on the
> latest Mathematica user version (I think it's 5.2) under
> Windows or Unix  and report the results:
>
> rho=(x+a*I)/(x-a*I); R=Abs[rho];
> s=Series[R,{x,0,4}];
> Print[FullSimplify[s,a>=0&&x>=0]//InputForm];
>
> My 5.0 answer (Mac G5 under OS 10.4.8) is
>
> SeriesData[x, 0, {1, (-2*I)/a, (-2*(1 + Derivative[Abs][-1]))/a^2,
> (((2*I)/3)*(3 + 6*Derivative[Abs][-1] - 2*Derivative[Abs][-1]))/
>    a^3, (2*(3 + 9*Derivative[Abs][-1] - 6*Derivative[Abs][-1] +
> Derivative[Abs][-1]))/(3*a^4)}, 0, 5, 1]
>
> The correct answer is 1. (The result with Simplify is more
> complicated.)  Thanks.
>

```