Re: Why is this so?
- To: mathgroup at smc.vnet.net
- Subject: [mg15334] Re: Why is this so?
- From: phbrf at t-online.de (Peter Breitfeld)
- Date: Fri, 8 Jan 1999 04:15:22 -0500
- Organization: das ist ein breites Feld ...
- References: <76pq9g$e0n@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Chester Lin <chester at nicco.sscnet.ucla.edu> schrieb:
> The following in/out does not make sense to me:
>
> Clear[f, x]
> f[x_] := x^(1/3)
> Plot[f[x], {x, -125, 125}]
>
>
> Isn't it true that (-125)^(1/3) == -5?
>
> Why do I get this strange result?
>
> I am using Mathematica 3.01 for Students on Macintosh.
Mathematica take the principal branch of root, so (-125)^(1/3) is
evaluated to 5/2 + 5 I Sqrt[3])/2
Es gruesst
Peter
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P e t e r B r e i t f e l d eMail: phbrf at t-online.de
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