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Re: wierd Log[0] *0 result

• To: mathgroup at smc.vnet.net
• Subject: [mg9125] Re: wierd Log[0] *0 result
• From: Bill Bertram <wkb at ansto.gov.au>
• Date: Mon, 13 Oct 1997 23:33:36 -0400
• Organization: ANSTO
• Sender: owner-wri-mathgroup at wolfram.com

Patrick Tao wrote:
> 
> Hello mma users,
> 
> I have a quick question on the following computation:
> 
> the natural log of 0 times 0 writen Log[0]*0
> 
> Should that not be 0 ?
> 
> mma is returning an Indeterminate result

 mma evaluates that as -Infinity times Zero and 
 doesn't know what kind of Infinity and what
 kind of Zero it is dealing with.

You should use something like

   Limit[x Log[x], x ->0]

which dous yield 0.

Cheers, Bill