VOCABULARY Monomial –a real number, a variable, or a product of real numbers and variables with whole number exponents Degree of a monomial – the exponent of the variable if there is only one variable, or the sum of the exponents if there is more than one variable Polynomial – a monomial or the sum of monomials Degree of a polynomial – the greatest degree among the monomial terms. Polynomial function – a polynomial in the variable x Standard form of a polynomial – arrange the terms by degree in descending numerical order. A polynomial function P(x), where n is a nonnegative integer and 𝑎𝑎𝑛,… ,𝑎𝑎0 are real numbers. Turning point –a point where the graph of a function changes direction from upwards to downwards or from downwards to upwards End behavior – the direction of the graph of a function as you move to the left and to the right, away from the origin. Factor theorem – the expression (x – a) is a linear factor of a polynomial if and only if the value of a is a root of the related polynomial function Multiple zero –if a linear factor is repeated in the complete factored form of a polynomial, the zero related to that factor is a multiple zero EX. (𝑥)=2𝑥(𝑥−3)2(𝑥+1) relative maximum – the y-value of the function at an up-to-down turning point. relative minimum – the y-value of the function at an down-to-up turning point. Sum of cubes – an expression in the form of 𝑎𝑎3+ 𝑏𝑏3. It can be factored as (𝑎+𝑏)(𝑎2− 𝑎+𝑏2) EX. 𝑥3+8 Difference of cubes – an expression in the form 𝑎𝑎3− 𝑏𝑏3. It can be factored as (𝑎−𝑏)(𝑎2+𝑎+𝑏2) EX. 𝑥3−27 Division Algorithm for Polynomials – Divide polynomial (𝑥) by polynomial 𝐷(𝑥) to get polynomial quotient 𝑄(𝑥) and polynomial remainder 𝑅𝑅(𝑥𝑥). The result is (𝑥)=𝐷(𝑥)𝑄(𝑥)+ 𝑅(𝑥). If 𝑅(𝑥)=0, then 𝑃(𝑥)=𝐷(𝑥)𝑄(𝑥) and 𝐷(𝑥) and 𝑄(𝑥) are factors of 𝑃(𝑥). Synthetic division – the process for dividing a polynomial by a linear expression x – a. A polynomial must be in standard form. By omitting all variables and exponents Remainder Theorem – If you divide a polynomial (𝑥) of degree 𝑛≥1 by x – a, then the remainder is 𝑃(𝑎). Rational Root Theorem – Any polynomial function with integer coefficients of the form (𝑥)= 𝑎𝑛𝑥𝑛+ 𝑎𝑛−1𝑥𝑛−1+ …+ 𝑎1𝑥+ 𝑎0 has a limited number of possible roots of 𝑃(𝑥)=0. Integer roots must be factors of 𝒂𝒂𝟎. Rational roots must have reduced form p/q where p is an integer factor of 𝒂𝒂𝟎𝟎 and q is an integer factor of 𝒂𝒂𝒏𝒏. Conjugate Root Theorem – If P(x) is a polynomial with rational coefficients, then the irrational roots of (𝑥)=0 occur in conjugate pairs. That is, when (𝑎+ √𝑏) is a root, then (𝑎− √𝑏) is also a root. Also, if 𝑎+𝑏 is a zero of a function, then 𝑎−𝑏 is also a zero. Descartes’ Rule of Signs – Let P(x) be polynomial with real coefficients written in standard form. • The number of positive real roots of (𝒙)= 𝟎 is either equal to the number of sign changes between consecutive coefficients of 𝑷(𝒙) or is less than that by an even number. • The number of negative real roots of (𝒙)= 𝟎 is either equal to the number of sign changes between consecutive coefficients of 𝑷(−𝒙) or is less than that by an even number. Fundamental Theorem of Algebra – If (𝑥) is a polynomial of degree 𝑛≥1 with complex coefficients, then 𝑃(𝑥)=0 has at least one complex root. Example: (𝑥)=3𝑥3− 2𝑥+3 is a polynomial of degree 3, so 𝑃(𝑥)=0 has at least one complex root. Every quadratic polynomial equation has two roots, every cubic polynomial equation has three roots, and so on. expand – the operation of multiplying a binomial to a specific power, then writing the polynomial in standard form. Pascal’s Triangle – A rectangular array of numbers in which the first and last number is 1. Each of the other numbers in the row is the sum of the two numbers above it. Binomial Theorem – For every positive integer n, (𝑎+𝑏)= 𝑃0𝑎𝑛+ 𝑃1𝑎𝑛−1 𝑏+𝑃2𝑎𝑛−2 𝑏2+ …+ 𝑃𝑛−1𝑎𝑛−1+𝑃𝑛𝑏𝑛, where 𝑃1,𝑃2, …,𝑃𝑛 are the numbers in the row of Pascal’s Triangle that has n as its second number.