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 Author Comment/Response Nasser M. Abbasi 12/12/12 08:07am This factorizes the polynomial alright, but not in the form P(x)=(x-r1)^p2*(x-r2)^p2*...*(x-rk)^pk with the r's being roots and p's respective algebraic multiplicities. Is it possible to have Mathematica factor the polynomial x^4+2x^2+1 to (x+I)^2*((x-I)^2)? ------------------------------------ I looked at the documentation and could not find a function. It seems like there should be one. May I missed it. But how about something like (quick hack, make sure to test more) ------------------------------- myFactor[p_, x_] := Module[{g, sol, lis}, sol = NSolve[p, x]; g = Gather[x /. sol, (Re[#1] == Re[#2]) && (Im[#1] == Im[#2]) &]; (x - First[#])^Length[#] & /@ g ] ---------------------- The above gives the factors in a list to use. You can Apply Plus to change the head (or use Total, etc... or anything else you want to do with them. To use: myFactor[x^4 + 2*x^2 + 1, x] // Rationalize // TableForm myFactor[x^8 + x^4 + 2*x^2 + 1, x] // Rationalize // TableForm etc... ps. warning, I am not a math major, so any errors, I am can't be held responsible ;) --Nasser URL: ,

 Subject (listing for 'Polynomial factorization by roots?') Author Date Posted Polynomial factorization by roots? Gandalf Saxe 12/11/12 11:08am Re: Polynomial factorization by roots? Nasser M. Ab... 12/12/12 08:07am Re: Polynomial factorization by roots? Gandalf 12/18/12 08:58am Re: Polynomial factorization by roots? Steve Keeley 12/25/12 7:44pm Re: Re: Polynomial factorization by roots? Steve Keeley 12/26/12 7:30pm Re: Polynomial factorization by roots? Steve Keeley 12/26/12 7:48pm Re: Re: Polynomial factorization by roots? Gandalf Saxe 12/28/12 05:36am Re: Re: Re: Polynomial factorization by roots? yehuda 12/28/12 11:39am Re: Re: Re: Polynomial factorization by roots? Steve Keeley 12/28/12 12:11pm Re: Re: Re: Polynomial factorization by roots? Steve Keeley 12/28/12 1:02pm Re: Re: Re: Re: Polynomial factorization by roo... yehuda 12/29/12 00:17am
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