You only need to add some assumptions to your expressions, since for some set
of values the Log[] is not defined
For example use
FullSimplify[Log[x^n] - n*Log[x], Assumptions -> x > 0 && n > 0]
and it will return 0 as expected
yehuda
On Sunday 30 January 2005 10:18, Cyrus Erik Eierud wrote:
> Please Help!
>
> Thanks for all great answers I've already found here!
> My problem is that I can not simplify what to me seems as a very
> simple equality task. This is what I want Mathematica to return zero
> for:
>
> in[1]:= FullSimplify[Log[x^n] - n*Log[x]]
>
> out[1]= -n Log[x] + Log[x^n])
>
> I have used Simplify to check equalities, but the one above (and many
> other equations similar to the one above) just don't simplify. Am I
> doing anything wrong or does anyone know of a better way to check
> equalities?
>
> Appreciate any help,
> Cyrus Eierud, Student
> cyruserik at tele2.se