AFAM Chapter 4

polynomial in one variable

A polynomial that contains no more than one different variable

degree of a polynomial

the greatest degree of any term in the polynomial

leading coefficient

The coefficient of the term with the highest degree

polynomial function

a function that is represented by a polynomial equation

zeros of a function

Values of the variable for which the value of a function is zero. Also called roots of a function.

polynomial equation

a polynomial that is set equal to zero

imaginary number

the square root of a negative number

root of an equation

a solution of an equation

complex number

a number of the form a+bi where a and b are real numbers and i is the square root of -1

Fundamental Theorem of Algebra

Every polynomial equation with degree greater than zero has at least one root in the set of complex numbers.

completing the square

a process used to make a quadratic expression into a perfect square trinomial

Quadratic Formula

x = -b � ?(b� - 4ac)/2a

discriminate of quadratic equation

b^2-4ac

Remainder Theorem

If a polynomial f(x) is divided by x-k, the remainder is r=f(k)

synthetic division

a method used to divide a polynomial by a binomial

Factor Theorem

The binomial x-r is a factor of the polynomial P(x) if and only if P(r)=0

depressed polynomial

the quotient when a polynomial is divided by one of its binomial factors

Rational Root Theorem

Identifies a list of possible zeroes of a polynomial function.

Integral Root Theorem

if the leading coefficient is one, then any rational roots must be factors of a sub n

Descartes' Rule of Signs

a technique for finding the number of positive and negative roots to a polynomial equation with real coefficients

location principle

A way of finding roots or zeros of a function

Upper Bound Theorem

Suppose c is a positive real number and P(x) is divided by x-c. If the resulting quotient and remainder have no change in sign then P(x) has no real zero greater than c. Thus c is an upper bound of the zeros of P(x)

upper bound

the highest value that a prediction is likely to be

lower bound

the lowest value that a prediction is likely to be