Equivalent quadratic expressions
A parametric family and sub-families

The expression

defines a family of quadratic functions: each choice of values for parameters a, b, c, d, e produces a different quadratic function. The family is represented in the dynamic figure below (which is a special case of the Parametric Families tool). By leaving some of the parameters fixed and changing some others, you obtain a family of functions that is a sub-family of the original family. You can construct many families in this way.


Produce:
- Sub-families generated by keeping four of the parameters fixed and changing one.
- Sub-families generated by keeping three of the parameters fixed and changing two.
- Conitnue reducing the number of fixed parameters and increasing the number of those that change.
Choose a family that looks interesting to you.

Describe the family you have chosen: What properties are common to all the functions in the family? What properties vary?
  • Write correspondence rules for several functions in the family you have chosen.
  • Write a general expression for your family, using only one parameter.
  • Explain the reasons behind the special properties of the family of functions you have chosen.


  • parametric expression
    f
    change
    trace
    =a
    =b
    =c
    =d
    =e






    Vertex Form
    Polynomial Form
    Product Form

    Reading information about functions
    Immunization against the common cold
    Numeric surprises
    Constructing functions
    Wage increase
    Partial pictures
    Examining value tables
    Families of functions
    Vertex paths
    Family and sub-families
    Parametric families

    Exercise 1
    Exercise 2
    Exercise 3
    Exercise 4
    Exercise 5
    Exercise 6
    Exercise 7
    Exercise 8
    Exercise 9
    Exercise 10
    Exercise 11
    Exercise 12