Re: Solutions of an equation under complex form

*To*: mathgroup at smc.vnet.net*Subject*: [mg54529] Re: [mg54478] Solutions of an equation under complex form*From*: Murray Eisenberg <murray at math.umass.edu>*Date*: Tue, 22 Feb 2005 04:24:00 -0500 (EST)*Organization*: Mathematics & Statistics, Univ. of Mass./Amherst*References*: <200502210844.DAA27204@smc.vnet.net>*Reply-to*: murray at math.umass.edu*Sender*: owner-wri-mathgroup at wolfram.com

In such situations, ComplexExpand is your friend! Thus: Solve [x^2 + x + 1 == 0, x] ComplexExpand[x /. %] // InputForm {-(1/2) - (I*Sqrt[3])/2, -(1/2) + (I*Sqrt[3])/2} Michaël Monerau wrote: > 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 -- Murray Eisenberg murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 549-1020 (H) University of Massachusetts 413 545-2859 (W) 710 North Pleasant Street fax 413 545-1801 Amherst, MA 01003-9305

**References**:**Solutions of an equation under complex form***From:*Michaël Monerau <mmonerau@gmail.com>