Re: Factor[1+x^4]
- To: mathgroup at smc.vnet.net
- Subject: [mg26871] Re: [mg26855] Factor[1+x^4]
- From: Andrzej Kozlowski <andrzej at tuins.ac.jp>
- Date: Fri, 26 Jan 2001 01:27:19 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
In my opinion at least, Mathematica does the right thing and requires you to specify the extension of the rationals over which you want to factor. This way is more flexible and powerful: In[1]:= Factor[x^4 + 1, Extension -> {I}] Out[1]= 2 2 (-I + x ) (I + x ) In[2]:= Factor[x^4 + 1, Extension -> {I, Sqrt[2]}] Out[2]= 1 - (Sqrt[2] - (1 + I) x) (Sqrt[2] - (1 - I) x) 4 (Sqrt[2] + (1 - I) x) (Sqrt[2] + (1 + I) x) and so on -- Andrzej Kozlowski Toyama International University JAPAN http://platon.c.u-tokyo.ac.jp/andrzej/ http://sigma.tuins.ac.jp/ on 01.1.25 3:13 PM, Tom Cage at k5gj at earthlink.net wrote: > I would like to factor 1+x^4. Mathematica 3 will only respond with > In[1]:= Factor[1+x^4] > Out[2]= 1+x^4 > > > Other systems will give the complex result > > 1+x^4 = (x+1/2*Sqrt(2)*I+1/2*Sqrt(2))* > (x+1/2*Sqrt(2)*I-1/2*Sqrt(2))* > (x-1/2*Sqrt(2)*I+1/2*Sqrt(2))* > (x-1/2*Sqrt(2)*I-1/2*Sqrt(2)) > > > How would I factor 1+x^4 with Mathematica > > > >