Re: Simplify problems for checking easy equalities...

*To*: mathgroup at smc.vnet.net*Subject*: [mg53859] Re: Simplify problems for checking easy equalities...*From*: "Scout" <user at domain.com>*Date*: Tue, 1 Feb 2005 04:08:10 -0500 (EST)*References*: <cti5nd$8n2$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

You have to use assumptions: In[1]:= Simplify[ Log[x^n] - n*Log[x], {x\[Element]Reals, x>0,n\[Element]Reals}] Out[1]:= 0 Log(x) is defined for real x in (0;Infinity) ~Scout~ "Cyrus Erik Eierud" <cyruserik at tele2.se> ha scritto nel messaggio news:cti5nd$8n2$1 at smc.vnet.net... > 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 >