[back] [prev] [next] [index] [root]

 


GaloisMSumPol

Computing of a polynomial of degree {n choose k} which roots are sums of k distinct roots of f.

Syntax:

g:= GaloisMSumPol(f, k);

int
  k  
must be positive
polynomial
  f,g  

See also:  GaloisGlobals, GaloisGroupsPossible, GaloisModulo, GaloisTree, GaloisRoots, GaloisNumberToName, GaloisBlocks

Description:

Let f be a monic polynomial of degree n in Q,Q(x) or a simple relative order.This function computes a primitive polynomial of degree {n choose k}. The roots of GaloisMSumPol are the sums of k distinct roots of f.


Example:


kash> o := OrderMaximal(Z, 2, 2);
Generating polynomial: x^2 - 2
Discriminant: 8 

kash> ox := PolyAlg(o);
Univariate Polynomial Ring in x over Generating polynomial: x^2 - 2
Discriminant: 8 

kash> f := Poly(ox, [Elt(o,1), Elt(o,[74,-16] / 73), Elt(o,[5988,-2368]
> / 5329), Elt(o, [160667739, -69612720] / 133432831), Elt(o,
> [98807254537, -54032137568] / 68184176641)]);
x^4 + [74, -16] / 73*x^3 + [5988, -2368] / 5329*x^2 + [160667739, -69612720] /\
 133432831*x + [98807254537, -54032137568] / 68184176641
kash> g := GaloisMSumPol(f,2);
> x^6 + (222/73*.1 - 48/73*.2)*x^5 + (29940/5329*.1 - 11840/5329*.2)*x^4 + (\
2594440/389017*.1 - 1355200/389017*.2)*x^3 + (42642475310/68184176641*.1 - \
42196712560/68184176641*.2)*x^2 + (-16578528081908/4977444894793*.1 + 988909\
5753408/4977444894793*.2)*x - 35497382888701141/17804320388674561*.1 + 22361\
191523984800/17804320388674561*.2


<- back[back] [prev] [next] [index] [root]