Re: proof of formula for log(-t) found in Mathematica?

*To*: mathgroup at smc.vnet.net*Subject*: [mg48203] Re: proof of formula for log(-t) found in Mathematica?*From*: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>*Date*: Tue, 18 May 2004 04:16:03 -0400 (EDT)*Organization*: Universitaet Leipzig*References*: <c89q4h$t5b$1@smc.vnet.net>*Reply-to*: kuska at informatik.uni-leipzig.de*Sender*: owner-wri-mathgroup at wolfram.com

Hi, consult a book on complex analysis ... Log[-t] -> Log[ Abs[t]*E^(I*Arg[-t])] -> Log[Abs[t]]+I*Arg[-t] -> Log[Sqrt[t^2]]+I*Arg[-t] -> Log[t^2]/2+I*Arg[-t] Regards Jens "Roger L. Bagula" wrote: > > I found this while doing work on complex exponents: > > f(t)=Log[-t]=Log[t^2]/2+I*Arg[-t] > > It is a result built into Mathematica. > I would like to see how it is derived as it seem counter intuitive in > it's results. > Respectfully, > Roger L. Bagula