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Re: Solutions of an equation under complex form

  • To: mathgroup at smc.vnet.net
  • Subject: [mg54494] Re: [mg54478] Solutions of an equation under complex form
  • From: Bob Hanlon <hanlonr at cox.net>
  • Date: Tue, 22 Feb 2005 04:22:53 -0500 (EST)
  • Reply-to: hanlonr at cox.net
  • Sender: owner-wri-mathgroup at wolfram.com

soln = Solve[x^2+x+1==0,x]/.
    x_?NumericQ:>Re[x]+I*Im[x]

{{x -> -(1/2) - (I*Sqrt[3])/2}, 
  {x -> -(1/2) + (I*Sqrt[3])/2}}


Bob Hanlon

> 
> From: Michaël Monerau <mmonerau at gmail.com>
To: mathgroup at smc.vnet.net
> Date: 2005/02/21 Mon AM 03:44:46 EST
> To: mathgroup at smc.vnet.net
> Subject: [mg54494] [mg54478] Solutions of an equation under complex form
> 
> Hello,
> 
> I'm running into a little problem under Mathematica 5.0 but I'm sure 
> people here will just take it as "too easy", but, well :) I just want 
> the solutions of the equation :
> 
> x^2 + x + 1 == 0
> 
> under their complex form.
> 
> So, I type :
> 
> Solve [x^2 + x + 1 == 0, x]
> 
> But I unfortunately get :
> { { {x -> -(-1)^(1/3) }, { x -> (-1)^(2/3) } } }
> 
> And I'd prefer to obtain the more "readable" form :
> -1/2 + I*1/2*Sqrt[3], -1/2 - I*1/2*Sqrt[3]
> 
> that I would get under another system for instance. What special function
> should I call to get this form under Mathematica ?
> 
> Thanks for any help
> -- 
> Michaël Monerau
> -= JJG =-
> 
> 


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