Re: all derivatives zero not imply zero!?

From: Virgil (ITSnetNOTcom#virgil_at_COMCAST.com)
Date: 10/23/04 

Date: Fri, 22 Oct 2004 23:34:10 -0600

In article <clcmgb$682$1@news.math.niu.edu>,
 rusin@vesuvius.math.niu.edu (Dave Rusin) wrote:

> In article <200410221247.i9MCl7N04243@proapp.mathforum.org>,
> G.E. Ivey <George.Ivey@gallaudet.edu> wrote:
>
> > Define f(x)= exp(-1/x^2) if x is not 0
> > 0 if x= 0
>
> OK, we all agree this is the canonical answer. Does anyone know
> (1) Who came up with this?
> (2) What was the canonical answer before this?
>
> dave

Unless the function itself is required to be zero at the point of
interest, which is not evident from the way the Subject is phrased, any
non-zero constant function will do.

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