[0-0-1-n1] Polynomials and Turning Points
def: polynomial - an expression consisting of variables (or indeterminates) and coefficients, that involves only the operations of addition, subtraction, multiplication, and non-negative integer exponents.
def: Degree of a Polynomial - the largest exponent of the polynomial
def: Turning Point - A point at which a graph changes directions. This happens at a peak or valley.
prop: If $n$ is the degree of a polynomial, then the polynomial can have at most $n - 1$ turning points
def: x-intecepts / zeros of a polynomial - the point(s) where a graph touches the x axis
prop: If $r$ is a zero of the graph of a polynomial, then $x - r$ is a factor of that polynomial
def: Multiplicity - given a polynomial in factored form, Multiplicity is the power of each factored piece.
example:
construct a polynomial of degree three whose zeros are $-2,0,2$. We are given three zeros, so we can form three factors.
$$ y = (x - (-2))(x - 0)(x - 2) $$
If we use multiplication to expand this expression in the usual way, we get
$$ y = x^3 - 4x $$
$$ \{ \mathbf{x_i}, y_i \} \qquad where \qquad i = 1 ... L, \quad y_i \in \{-1,1\}, \quad \mathbf{x} \in \mathfrak{R}^D $$
- http://sites.csn.edu/ehutchinson/Notes/3_2NOTES124.pdf
wikis http://tutorial.math.lamar.edu/Classes/Alg/Factoring.aspx https://en.wikipedia.org/wiki/Polynomial_ring https://en.wikipedia.org/wiki/Irreducible_polynomial https://en.wikipedia.org/wiki/Factorization_of_polynomials https://en.wikipedia.org/wiki/Factor_theorem