Re: notation help: f(x) = (sin x)^(1/3)

*To*: mathgroup at smc.vnet.net*Subject*: [mg29968] Re: [mg29947] notation help: f(x) = (sin x)^(1/3)*From*: Andrzej Kozlowski <andrzej at tuins.ac.jp>*Date*: Fri, 20 Jul 2001 03:28:31 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

First of all you do have a syntax error. What you meant was: Plot[Sin[x]^(1/3), {x, -10, 10}] But actually this will also not work. The explanation is again: complex functions or your lack of acquaintance with them. The point is that x^(1/3) is not what you think it is when x is a negative real number (it is a complex number). There are several ways round it. One of them is to load the <<Miscellaneous`RealOnly` package. My preferred way is to use: Plot[Root[#^3-Sin[x]&,1], {x, -10, 10}] Here Root[#^3-Sin[x]&,1] means the real cube root of Sin[x]. -- Andrzej Kozlowski Toyama International University JAPAN http://platon.c.u-tokyo.ac.jp/andrzej/ http://sigma.tuins.ac.jp/~andrzej/ on 01.7.19 4:57 PM, Tim 9-23 at bendoftimeb at stny.rr.com wrote: > How do I plot this. I must not be entering it correctly. It's the > plot of the cube root of the Sine function. > > Plot[[Sin[x]]^(1/3), {x, -10, 10}] isn't working. Thanks. > > My email address is anti-spammed. Remove the 2 B's after hitting email reply > if you want to email me. > > Tim 9-23 > >