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TopNewestA note: logarithms

canbe extended for negative numbers if you consider complex numbers. See here.Log in to reply

More accurately, logarithms can be extended to all non-zero complex numbers.

You have to be careful, as it is no longer a one-to-one function, but multivalued (which some people do not consider as a function).

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log of a negative number is possible for some negative bases. However, the graph would break several times while sketching y=log x ( x<0 ) for a particular negative base. Thus we aptly say log of negative number is not possible.

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