1. Obj: graph parabolas in two forms
Chapter 3
3.1 Quadratic Functions
Obj: graph parabolas in two forms
and find the max or min

2. Quadratic Functions Review Quadratic form Solving a quadratic Graph
Vertex
Axis of Symmetry
Standard Form

3. Finding Standard Form
Given the function find the standard form by completing the square.
1. Factor a from the first two terms.
2. Complete the square as in last chapter.
3. Keep the equation in balance!
4. Factor the square and simplify.
5. Standard form

4. Find Vertex and Axis of Symmetry
Standard form
vertex at (h, k)
vertex = ( , )
axis of symmetry at x = h
axis at x =
Quadratic form
vertex at
axis of symmetry at x = -b/2a

5. Maximum and Minimum The max or min is the y-value of the vertex.
If a > 0, the function has a minimum.
If a < 0, the function has a maximum.
To find the max or min:
find the vertex by one of the previous
methods or . .
Use the graphing calculator

6. Example
Find the maximum or minimum value of the quadratic function. State whether the value is a maximum or minimum. By hand: With calculator:

7. Assignment
Page – 41 e.o.o., 59, 65