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Re: Abs[x] function

• To: mathgroup at smc.vnet.net
• Subject: [mg87845] Re: Abs[x] function
• From: Szabolcs <szhorvat at gmail.com>
• Date: Fri, 18 Apr 2008 07:10:27 -0400 (EDT)
• References: <fu9fn7$c8d$1@smc.vnet.net>

On 18 Apr, 08:39, Vladislav <kazimi... at yahoo.co.uk> wrote:
> Who can explain the behavior. THe derivative Abs[x] at x=.5 is well
> defined and is equal to 1.
>
> In[1]:= D[Abs[x], x]
>
> Out[1]=
> \!\(\*SuperscriptBox["Abs", "\[Prime]",
> MultilineFunction->None]\)[x]
>
> In[2]:= % /. x -> .5
>
> Out[2]=
> \!\(\*SuperscriptBox["Abs", "\[Prime]",
> MultilineFunction->None]\)[0.5]

Hi,

Please use "copy as plain text" when pasting Mathematica expressions,
so it will be easier to read them.

Just use FunctionExpand on the result to get a concrete value.

• Follow-Ups:
  • Re: Re: Abs[x] function
    • From: "Szabolcs HorvÃt" <szhorvat@gmail.com>
  • Re: Re: Abs[x] function
    • From: Andrzej Kozlowski <akoz@mimuw.edu.pl>