Re: branch of (-1)^(1/3)
- To: mathgroup at smc.vnet.net
- Subject: [mg94490] Re: [mg94405] branch of (-1)^(1/3)
- From: Carl Woll <carlw at wolfram.com>
- Date: Sun, 14 Dec 2008 07:41:58 -0500 (EST)
- References: <200812121154.GAA27892@smc.vnet.net>
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 > > > I assume you mean a simple way to choose the branch of a^(1/3), where a is real. If so, you can use: Root[#^3-a&, 1] Carl Woll Wolfram Research
- References:
- branch of (-1)^(1/3)
- From: "slawek" <human@site.pl>
- branch of (-1)^(1/3)