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Re: Limit bug in Calculus\Limit ???

• To: mathgroup at smc.vnet.net
• Subject: [mg8543] Re: [mg8488] Limit bug in Calculus\Limit ???
• From: Robert Pratt <rpratt at math.unc.edu>
• Date: Sat, 6 Sep 1997 23:16:11 -0400
• Sender: owner-wri-mathgroup at wolfram.com

The (two-sided) limit is not defined.  The (one-sided) limit IS defined as
y approaches 0 from the right (i.e. y>0), and this limit is infinity.
Also, the (one-sided) limit IS defined as y approaches 0 from the left
(i.e. y<0), and this limit is 0.  Since the one-sided limits don't agree,
the two-sided limit does not exist.

Rob Pratt
Department of Mathematics
The University of North Carolina at Chapel Hill
CB# 3250, 331 Phillips Hall
Chapel Hill, NC  27599-3250

rpratt at math.unc.edu

http://www.math.unc.edu/Grads/rpratt/

On Tue, 2 Sep 1997, Lars A. Stole wrote:

> I am using Mma 3.0 on a NextStep 3.3 PentiumPro Intel machine;  I 
> have also successfully reproduced the problem on a Sparc running Mma 
> 3.0.  
> 
> The following command
> 
> 	Limit[E^(2/y),y->0]
> 
> returns the correct answer "infinity" when the Calculus`Limit` 
> package IS NOT loaded.  When the Limit package IS_loaded (which I had 
> thought meant even more functionality), I incorrectly obtain "0" as 
> the answer.
> 
> Why is the Limit.m generating an incorrect answer?  Is this a known 
> bug?  And if so, is there a list of known bugs that a user can 
> access? 
> 
> Thanks.
> 
>