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					                                        Polynomials

Polynomials
A polynomial is an expression of finite length constructed from variables (also called indeterminates)
and constants, using only the operations of addition, subtraction, multiplication, and non-negative
integer exponents. However, the division by a constant is allowed, because the multiplicative inverse of
a non zero constant is also a constant. For example, x2 − x/4 + 7 is a polynomial, but x2 − 4/x + 7x3/2
is not, because its second term involves division by the variable x (4/x), and also because its third term
contains an exponent that is not an integer (3/2). The term "polynomial" can also be used as an
adjective, for quantities that can be expressed as a polynomial of some parameter, as in polynomial
time, which is used in computational complexity theory.

Polynomial comes from the Greek poly, "many" and medieval Latin binomium, "binomial".[1][2][3]
The word was introduced in Latin by Franciscus Vieta. Polynomials appear in a wide variety of areas of
mathematics and science. For example, they are used to form polynomial equations, which encode a
wide range of problems, from elementary word problems to complicated problems in the sciences; they
are used to define polynomial functions, which appear in settings ranging from basic chemistry and
physics to economics and social science; they are used in calculus and numerical analysis to
approximate other functions. In advanced mathematics, polynomials are used to construct polynomial
rings, a central concept in abstract algebra and algebraic geometry.

                                Know More About :- Multiplication Identity Property


    Math.Edurite.com                                                            Page : 1/3
A polynomial is either zero or can be written as the sum of a finite number of non-zero terms. Each
term consists of the product of a constant (called the coefficient of the term) and a finite number of
variables (usually represented by letters), also called indeterminates, raised to whole number powers.[5]
The exponent on a variable in a term is called the degree of that variable in that term; the degree of the
term is the sum of the degrees of the variables in that term, and the degree of a polynomial is the largest
degree of any one term. Since x = x1, the degree of a variable without a written exponent is one. A term
with no variables is called a constant term, or just a constant; the degree of a (nonzero) constant term is
0. The coefficient of a term may be any number from a specified set. If that set is the set of real
numbers, we speak of "polynomials over the reals". Other common kinds of polynomials are
polynomials with integer coefficients, polynomials with complex coefficients, and polynomials with
coefficients that are integers modulo of some prime number p. In most of the examples in this section,
the coefficients are integers.

In general any expression can be considered a polynomial if it is built from variables and constants
using only addition, subtraction, multiplication, and raising expressions to whole number powers. Such
an expression can always be rewritten as a sum of terms. For example, (x + 1)3 is a polynomial; its
standard form is x3 + 3x2 + 3x + 1. However, in some situations, a more accurate terminology is
needed in order to not be confusing. In such a case, one should say: (x + 1)3 is a polynomial expression
which may be expanded or rewritten into the polynomial x3 + 3x2 + 3x + 1. Although different as
expressions, these two expressions are equal in the ring of the polynomials in the indeterminate x with
integer coefficients.

As for the integers, two kinds of divisions are considered for the polynomials. The Euclidean division
that generalizes the Euclidean division of the integers. It results in two polynomials, a quotient and a
remainder that are characterized by the following property of the polynomials: given two polynomials a
and b such that b ≠ 0, there exists a unique pair of polynomials, q, the quotient, and r, the remainder,
such that a = b q + r and degree(r) < degree(b) (here the polynomial zero is supposed to have a negative
degree). By hand as well as with a computer, this division can be computed by the polynomial long
division algorithm. A formal quotient of polynomials, that is, an algebraic fraction where the numerator
and denominator are polynomials, is called a "rational expression" or "rational fraction" and is not, in
general, a polynomial. Division of a polynomial by a number, however, does yield another polynomial.

                                                         Read More About :- Addition Column


    Math.Edurite.com                                                             Page : 2/3
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