
Asymptote
A line that a function approaches but never intersects.

Axis
The line of symmetry of a parabola.

Constant Function
A polynomial function of degree zero in which the constant term ≠ 0.

Constant Term
The coefficient of x^{0} in a polynomial.

Degree
The value of n in a polynomial f (x) = a_{n}x^{n} + a_{n1}x^{n1} + ^{ ... } + a_{1}x + a_{0}, where a_{n}≠ 0. If f (x) = 0, then the degree is undefined.

Descartes' Rule of Signs
Descartes' Rule of Signs states that the number of positive real roots is less than or equal to the number of variations in the function f (x). It also states that the number of negative real roots is less than or equal to the number of variations in the function f ( x).

Leading Coefficient
The value of a_{n} in a polynomial f (x) = a_{n}x^{n} + a_{n1}x^{n1} + ^{ ... } + a_{1}x + a_{0}, where a_{n}≠ 0 unless f (x) = 0.

Linear Function
A firstdegree polynomial.

Multiplicity
If (x  c)^{n} is a factor of a polynomial but (x  c)^{n+1} is not, the root c is said to be a root of multiplicity n.

Parabola
Another name for the graph of a quadratic function.

Polynomial
An expression of one variable of the form a_{n}x^{n} + a_{n1}x^{n1} + ^{ ... } + a_{2}x^{2} + a_{1}x + a_{0}, where a_{n}, a_{n1},..., a_{1}, a_{0} are real numbers, n is a nonnegative integer, and a_{n}≠ 0.

Polynomial Function
A function that is defined by a polynomial; it is of the form f (x) = a_{n}x^{n} + a_{n1}x^{n1} + ^{ ... } + a_{2}x^{2} + a_{1}x + a_{0}, where a_{n}, a_{n1},…, a_{1}, a_{0} are real numbers, n is a nonnegative integer, and a_{n}≠ 0.

Quadratic Function
A seconddegree polynomial.

Rational Function
A function which can be expressed as the quotient of two polynomial functions.

Rational Root Theorem
The Rational Root Theorem is a useful tool in finding the roots of a polynomial function f (x) = a_{n}x^{n} + a_{n1}x^{n1} + ... + a_{2}x^{2} + a_{1}x + a_{0}. If the coefficients of a polynomial are all integers, and a root of the polynomial is rational (it can be expressed as a fraction in lowest terms), the Rational Root Theorem states that the numerator of the root is a factor of a_{0} and the denominator of the root is a factor of a_{n}.

Root
Values of the independent variable for which a polynomial function equals zero.

Variation
Consecutive terms of a polynomial whose coefficients have opposite signs.

Vertex
The point on a parabola at which the quadratic function reaches its minimum or maximum value.

Zero Polynomial
The polynomial f (x) = 0.
Terms
Formulae
Quadratic Formula  If ax^{2} + bx + c = 0, then x = . 