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Re: a simplification problem

• To: mathgroup at smc.vnet.net
• Subject: [mg55248] Re: [mg55172] a simplification problem
• From: Bob Hanlon <hanlonr at cox.net>
• Date: Thu, 17 Mar 2005 03:30:29 -0500 (EST)
• Reply-to: hanlonr at cox.net
• Sender: owner-wri-mathgroup at wolfram.com

It isn't equal to -1

(-1)^(1/3)//N

0.5000000000000001 + 0.8660254037844386*I

You want a real x such that x^3 is -1

Reduce[x^3==-1,x,Reals]

x == -1

Simplify[x^3==-1,Element[x,Reals]]

x == -1


Bob Hanlon

> 
> From: Hui Fang <fangh73 at xmu.edu.cn>
To: mathgroup at smc.vnet.net
> Date: 2005/03/16 Wed AM 05:35:49 EST
> To: mathgroup at smc.vnet.net
> Subject: [mg55248] [mg55172] a simplification problem
> 
> Dear All,
> 
> My questions is simple:
> How do I simplify (-1)^(1/3) to -1?
> 
> Thanks!
> 
> 

Bob Hanlon
Chantilly, VA