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 Author Comment/Response Peter Pein 09/25/09 5:41pm Hi Nick, if you want exact expressions without "I", you could try ComplexExpand: In[1]:= sol = TrigExpand[Solve[x^3 + x^2 - 8*x + 1 == 0, x] /. (x -> r_) :> x -> ComplexExpand[r, TargetFunctions -> {Abs, Arg}]] Out[1]= {{x -> -(1/3) + (5/3)* Cos[(1/3)*ArcTan[(3*Sqrt[5811])/101]] + (5*Sin[(1/3)*ArcTan[(3*Sqrt[5811])/101]])/ Sqrt[3]}, {x -> -(1/3) + (5/3)* Cos[(1/3)*ArcTan[(3*Sqrt[5811])/101]] - (5*Sin[(1/3)*ArcTan[(3*Sqrt[5811])/101]])/ Sqrt[3]}, {x -> -(1/3) - (10/3)* Cos[(1/3)*ArcTan[(3*Sqrt[5811])/101]]}} In[2]:= N[x /. %] Out[2]= {2.2954157235909167, 0.12728287906017538, -3.4226986026510926} Peter URL: ,

 Subject (listing for 'Solving Polynomials') Author Date Posted Solving Polynomials Nick 09/19/09 4:58pm Re: Solving Polynomials TomD 09/21/09 6:32pm Re: Solving Polynomials yehuda ben-s... 09/22/09 08:31am Re: Solving Polynomials Peter Pein 09/25/09 5:41pm Re: Solving Polynomials Peter Pein 09/25/09 5:48pm
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