limit(log(x),x,0)?



On 01/26/2010 01:49 PM, Raymond Toy wrote:
> What is limit(log(x),x,0)?  Maxima currently returns infinity.  I
> suppose that's correct, but with a default domain of real, shouldn't
> this be undefined?
>
> Ray
>
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>    
In the complex case, 'log' requires the choice of branches of Arg, so I 
assume we are dealing with only real x.

If you draw the graph of log(x), then you see that it is monotone 
increasing and only defined for real x > 0.  So, the only meaning can be

  lim_{x -> 0+} log(x).

Then, the numbers log(x) approach -Infinity, so I think the answer 
should actually be
    limit(log(x),x,0) = -Infinity  (that is minus infinity).

-sen