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4.2 STANDARD FORM OF A
QUADRATIC FUNCTION
Part 1: Properties of Standard Form and Graphing
using Standard Form
QUADRATIC FUNCTIONS
   Vertex Form:

   Standard Form is another way to write the
    equation of a quadratic function.
    Standard form is:



        Both forms can represent the same function. Vertex
        form makes it easy to identify the vertex and other
        information about the graph. Standard form is easier
        to put into a graphing calculator and is more “formal”.
PROPERTIES OF STANDARD FORM

   The graph of                          is a parabola.

   If a > 0, the graph opens up. If a < 0, the graph
    opens down.

   The axis of symmetry is the line

   The x – value of the vertex is        and the y –
    value of the vertex is

   The y – intercept is (0, c)
EXAMPLE: IDENTIFY THE VERTEX, AXIS OF
SYMMETRY, THE MAXIMUM OR MINIMUM VALUE, AND
THE RANGE OF THE PARABOLA
EXAMPLE: IDENTIFY THE VERTEX, AXIS OF
SYMMETRY, THE MAXIMUM OR MINIMUM VALUE, AND
THE RANGE OF THE PARABOLA
GRAPHING A FUNCTION IN STANDARD FORM
1.   Identify a, b, and c
2.   Identify and sketch the axis of symmetry,
3.   Identify and plot the vertex,

4.   Identify and plot the y – intercept, (0, c)
5.   Use the axis of symmetry and y – intercept to plot
     the reflected point
6.   Sketch the parabola
GRAPH EACH FUNCTION
GRAPH EACH FUNCTION