Wednesday, August 11

division algorithm


Let us learn about division algorithm

In mathematics, polynomials in more than one variable do not form a Euclidean domain, so it is not possible to construct a true division algorithm. Given a polynomial g, polynomials (f1, ..., fm) and an order on the monomials in k[x1, ..., xn], we construct the reduction of g modulo f1, ..., fm by the following algorithm. Let ai denote the leading term of fi with respect to the monomial order. Repeatedly apply the following until no monomial term of g is divisible by any of the ai :
Division Algorithm for Polynomials

Let F is a field, f(x), g(x) e F[x] with g(x) ≠ 0.

In q(x), r(x) in the F[x] such that f(x) = g(x) q(x) + r(x) and r(x) =0

Proof :-
(1) Let f(x) = g(x) q(x) + r(x) with g(x) ≠ 0

(2) If f(x) = 0 or deg f(x) is less than g(x), then r(x)=f(x), q(x)=0.

(3) So, we assume that f(x) ≠ 0 and deg f(x) ≥ deg g(x)

(4) Let f(x) = anxn + ... + a0

(5) Let g(x) = bmxm + ... + b0

(6) Let f1(x) = f(x) - anbm-1xn-mg(x)

(7) We note that deg f1(x) is <>deg f(x) since:

f(x) - anbm-1xn-mg(x)

= anxn + ... + a0 - anbm-1xn-m(bmxm + ... + b0)

= ann - anxn + an-1xn-1 + ... + a0 - anbm-1bm-1xn-1 - ... - anbm-1b0xn-m

= an-1xn-1 + ... + a0 - anbm-1bm-1xn-1 - ... - anbm-1b0xn-m

So that f1(x) has a degree of n-1 while f(x) has a degree of n.
In our next blog we shall learn about cleavage furrow I hope the above explanation was useful.Keep reading and leave your

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