Unique factorization theorem

The polynomial analog of the fundamental theorem of arithmetic for the integers is the unique factorization theorem.

Theorem 2.4.4 (Unique factorization theorem)   Let $ F$ be a field and $ p(x)\in F[x]$. Then there are monic irreducible polynomials $ p_i(x)\in F[x]$, integers $ e_i>0$, $ i=1,2,...,k$, and a constant $ c\in F^\times$ such that

$\displaystyle f(x)=cp_1(x)^{e_1}...p_k(x)^{e_k}.
$

Furthermore, this expression is unique up to order.

proof: The proof is analogous to the proof of the fundamental theorem of arithmetic. It is therefore omitted. $ \Box$



David Joyner 2007-09-03