Paul Schlie <[EMAIL PROTECTED]> writes:

| > Gabriel Dos Reis wrote:
| > You probably noticed that in the polynomial expansion, you are using
| > an integer power -- which everybody agrees on yield 1 at the limit.
| >
| > I'm tlaking about 0^0, when you look at the limit of function x^y
| 
| Out of curiosity, on what basis can one conclude:
| 
|  lim{|x|==|y|->0} x^y :: lim{|x|==|y|->0} (exp (* x (log y))) != 1 ?

The issue is not whether the limit of x^x, as x approaches 0, is 1 not.
We all, mathematically, agree on that.

The issue is whether the *bivariate* function x^y has a defined limit
at (0,0).  And the answer is unambiguously no.  
Checking just one path does NOT suffice to assrt that the limit
exists. (However, that might suffice to assert that a limit does not
exist). 

I'm deeply burried somewhere in the middle-west deserts and I have no
much reliable connection, so I'll point you to the message

    http://gcc.gnu.org/ml/gcc/2005-03/msg00469.html 

where I've tried to taint this discussion with some realities from what
standard bodies think on the 0^0 arithmetic, and conterexample you can
check by yourself.

| As although it's logarithmic decomposition may yield intermediate complex
| values, and may diverge prior to converging as they approach their limit,
| it seems fairly obvious that the expression converges to the value of 1

You've transmuted the function x^y to the function x^x which is a
different beast.  Existing of limit of the latter does not imply
existance of limit of the former.  Again check the counterexamples in
the message I referred to above. 

-- Gaby

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