Re: branch of (-1)^(1/3)
- To: mathgroup at smc.vnet.net
- Subject: [mg94480] Re: [mg94405] branch of (-1)^(1/3)
- From: Murray Eisenberg <murray at math.umass.edu>
- Date: Sun, 14 Dec 2008 07:40:05 -0500 (EST)
- Organization: Mathematics & Statistics, Univ. of Mass./Amherst
- References: <200812121154.GAA27892@smc.vnet.net>
- Reply-to: murray at math.umass.edu
Can you say in what sort of context you want -1 to be returned? After all, the result returned from (-1)^(1/3) is just the Input expression itself. And, as taking N of the result shows, the value is, indeed, the principal cube-root of -1. slawek wrote: > Is a simple way to choose the branch of (-1)^(1/3) ? > > Mathematica gives a (correct) non-real answer. It is ok, but I need the (-1) > as the output when I input (1)^(1/3) because I know that it is a solution > of real-valued problem. > > Is any "standard way" to pick up a correct (i.e. arbitrary) root of > (-1)^(1/n) instead the default? > > slawek > > -- Murray Eisenberg murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 549-1020 (H) University of Massachusetts 413 545-2859 (W) 710 North Pleasant Street fax 413 545-1801 Amherst, MA 01003-9305
- References:
- branch of (-1)^(1/3)
- From: "slawek" <human@site.pl>
- branch of (-1)^(1/3)