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Re: a simplification problem


In article <d1bgl8$lpn$1 at smc.vnet.net>, DrBob <drbob at bigfoot.com> 
wrote:

> If you mean, "How do I extract the real third root of -1?", here's a method:
> 
> ComplexExpand[x /. Solve[x^3 == -1]]
> 
> {-1, 1/2 + (I*Sqrt[3])/2, 1/2 - (I*Sqrt[3])/2}
> 
> First@Select[%, FreeQ[#1, Complex] & ]
> 
> -1

To extract the real third root of -1, how about

  Root[#^3 + 1 & , 1]

Cheers,
Paul

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