ON THE DECOMPOSITION OF xd+aexe+···+a1x+a0
نویسنده
چکیده
Let K denote a field. A polynomial f(x) ∈ K[x] is said to be decomposable over K if f(x)= g(h(x)) for some polynomials g(x) and h(x)∈K[x] with 1< deg(h) < deg(f ). Otherwise f(x) is called indecomposable. If f(x)= g(xm) with m> 1, then f(x) is said to be trivially decomposable. In this paper, we show that xd+ax+b is indecomposable and that if e denotes the largest proper divisor of d, then xd+ad−e−1xd−e−1+···+ a1x+a0 is either indecomposable or trivially decomposable. We also show that if gd(x,a) denotes the Dickson polynomial of degreed and parametera and gd(x,a)= f(h(x)), then f(x)= gt(x−c,a) and h(x)= ge(x,a)+c
منابع مشابه
Graded Integral Domains and Nagata Rings , Ii
Let D be an integral domain with quotient field K, X be an indeterminate over D, K[X] be the polynomial ring over K, and R = {f ∈ K[X] | f(0) ∈ D}; so R is a subring of K[X] containing D[X]. For f = a0 + a1X + · · ·+ anX ∈ R, let C(f) be the ideal of R generated by a0, a1X, . . . , anX n and N(H) = {g ∈ R | C(g)v = R}. In this paper, we study two rings RN(H) and Kr(R, v) = { fg | f, g ∈ R, g 6=...
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