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Re: Differentiability
Posted:
Feb 21, 2013 6:37 AM


On 21/02/2013 04:13, William Elliot wrote: > A problem from > http://at.yorku.ca/cgibin/bbqa?forum=ask_an_analyst&task=list > > Suppose f(x)= e^(1/x^2) for x not equal to 0, and f(0)=0. > > Without using l'hopital's rule, prove f is differentiable at 0 and > that f'(0)=0.
This is a very standard example.
A tougher problem would be to prove this *using* The Hospital's rule :)



