POLYNOMIAL FUNCTIONS

A POLYNOMIAL is a monomial
    or a sum of monomials.

  A POLYNOMIAL IN ONE
VARIABLE is a polynomial that
  contains only one variable.
    Example: 5x2 + 3x - 7
POLYNOMIAL FUNCTIONS
The DEGREE of a polynomial in one variable is
     the greatest exponent of its variable.

A LEADING COEFFICIENT is the coefficient
    of the term with the highest degree.

    What is the degree and leading
     coefficient of 3x5 – 3x + 2 ?
POLYNOMIAL FUNCTIONS
   A polynomial equation used to represent a
function is called a POLYNOMIAL FUNCTION.
Polynomial functions with a degree of 1 are called
    LINEAR POLYNOMIAL FUNCTIONS

Polynomial functions with a degree of 2 are called
 QUADRATIC POLYNOMIAL FUNCTIONS
Polynomial functions with a degree of 3 are called
     CUBIC POLYNOMIAL FUNCTIONS
POLYNOMIAL FUNCTIONS
EVALUATING A POLYNOMIAL FUNCTION

    Find f(-2) if f(x) = 3x2 – 2x – 6

         f(-2) = 3(-2)2 – 2(-2) – 6
             f(-2) = 12 + 4 – 6
                 f(-2) = 10
POLYNOMIAL FUNCTIONS
EVALUATING A POLYNOMIAL FUNCTION

    Find f(2a) if f(x) = 3x2 – 2x – 6

         f(2a) = 3(2a)2 – 2(2a) – 6
           f(2a) = 12a2 – 4a – 6
POLYNOMIAL FUNCTIONS
EVALUATING A POLYNOMIAL FUNCTION

   Find f(m + 2) if f(x) = 3x2 – 2x – 6
     f(m + 2) = 3(m + 2)2 – 2(m + 2) – 6

  f(m + 2) = 3(m2 + 4m + 4) – 2(m + 2) – 6
  f(m + 2) = 3m2 + 12m + 12 – 2m – 4 – 6
         f(m + 2) = 3m2 + 10m + 2
POLYNOMIAL FUNCTIONS
EVALUATING A POLYNOMIAL FUNCTION

   Find 2g(-2a) if g(x) = 3x2 – 2x – 6
      2g(-2a) = 2[3(-2a)2 – 2(-2a) – 6]

        2g(-2a) = 2[12a2 + 4a – 6]
         2g(-2a) = 24a2 + 8a – 12
POLYNOMIAL FUNCTIONS
        GENERAL SHAPES OF
      POLYNOMIAL FUNCTIONS

  f(x) = 3
 Constant
 Function
 Degree = 0

Max. Zeros: 0
POLYNOMIAL FUNCTIONS
        GENERAL SHAPES OF
      POLYNOMIAL FUNCTIONS

 f(x) = x + 2
   Linear
  Function
 Degree = 1
Max. Zeros: 1
POLYNOMIAL FUNCTIONS
          GENERAL SHAPES OF
        POLYNOMIAL FUNCTIONS

f(x) = x2 + 3x + 2
   Quadratic
   Function
   Degree = 2
 Max. Zeros: 2
POLYNOMIAL FUNCTIONS
          GENERAL SHAPES OF
        POLYNOMIAL FUNCTIONS

f(x) = x3 + 4x2 + 2
     Cubic
    Function
   Degree = 3
 Max. Zeros: 3
POLYNOMIAL FUNCTIONS
          GENERAL SHAPES OF
        POLYNOMIAL FUNCTIONS

f(x) = x4 + 4x3 – 2x – 1
    Quartic
    Function
   Degree = 4
 Max. Zeros: 4
POLYNOMIAL FUNCTIONS
           GENERAL SHAPES OF
         POLYNOMIAL FUNCTIONS
f(x) = x5 + 4x4 – 2x3 – 4x2 + x – 1

     Quintic
    Function
   Degree = 5
  Max. Zeros: 5
POLYNOMIAL FUNCTIONS
             END BEHAVIOR

                         f(x) = x2
Degree: Even
Leading Coefficient: +
End Behavior:
As x  -∞; f(x)  +∞
As x  +∞; f(x)  +∞
POLYNOMIAL FUNCTIONS
             END BEHAVIOR

                         f(x) = -x2
Degree: Even
Leading Coefficient: –
End Behavior:
As x  -∞; f(x)  -∞
As x  +∞; f(x)  -∞
POLYNOMIAL FUNCTIONS
             END BEHAVIOR

                         f(x) = x3
Degree: Odd
Leading Coefficient: +
End Behavior:
As x  -∞; f(x)  -∞
As x  +∞; f(x)  +∞
POLYNOMIAL FUNCTIONS
             END BEHAVIOR

                         f(x) = -x3
Degree: Odd
Leading Coefficient: –
End Behavior:
As x  -∞; f(x)  +∞
As x  +∞; f(x)  -∞
REMAINDER AND FACTOR
           THEOREMS

f(x) = 2x2 – 3x + 4
Divide the polynomial by x – 2
                        Find f(2)
  2    2   -3   4     f(2) = 2(2)2 – 3(2) + 4
            4   2
                      f(2) = 8 – 6 + 4
       2    1   6     f(2) = 6
REMAINDER AND FACTOR
      THEOREMS
 When synthetic division is used to
  evaluate a function, it is called
 SYNTHETIC SUBSTITUTION.
Try this one:
Remember – Some terms are missing
       f(x) = 3x5 – 4x3 + 5x - 3
           Find f(-3)
REMAINDER AND FACTOR
     THEOREMS

     FACTOR THEOREM
 The binomial x – a is a factor of the
polynomial f(x) if and only if f(a) = 0.
REMAINDER AND FACTOR
          THEOREMS

     Is x – 2 a factor of x3 – 3x2 – 4x + 12

 2     1   -3   -4 12
                -2 -12     Yes, it is a factor,
            2
                            since f(2) = 0.
       1   -1   -6 0

Can you find the two remaining factors?
REMAINDER AND FACTOR
        THEOREMS


  (x + 3)( ? )( ? ) = x3 – x2 – 17x - 15

Find the two unknown ( ? ) quantities.

Polynomial functions

  • 1.
    POLYNOMIAL FUNCTIONS A POLYNOMIALis a monomial or a sum of monomials. A POLYNOMIAL IN ONE VARIABLE is a polynomial that contains only one variable. Example: 5x2 + 3x - 7
  • 2.
    POLYNOMIAL FUNCTIONS The DEGREEof a polynomial in one variable is the greatest exponent of its variable. A LEADING COEFFICIENT is the coefficient of the term with the highest degree. What is the degree and leading coefficient of 3x5 – 3x + 2 ?
  • 3.
    POLYNOMIAL FUNCTIONS A polynomial equation used to represent a function is called a POLYNOMIAL FUNCTION. Polynomial functions with a degree of 1 are called LINEAR POLYNOMIAL FUNCTIONS Polynomial functions with a degree of 2 are called QUADRATIC POLYNOMIAL FUNCTIONS Polynomial functions with a degree of 3 are called CUBIC POLYNOMIAL FUNCTIONS
  • 4.
    POLYNOMIAL FUNCTIONS EVALUATING APOLYNOMIAL FUNCTION Find f(-2) if f(x) = 3x2 – 2x – 6 f(-2) = 3(-2)2 – 2(-2) – 6 f(-2) = 12 + 4 – 6 f(-2) = 10
  • 5.
    POLYNOMIAL FUNCTIONS EVALUATING APOLYNOMIAL FUNCTION Find f(2a) if f(x) = 3x2 – 2x – 6 f(2a) = 3(2a)2 – 2(2a) – 6 f(2a) = 12a2 – 4a – 6
  • 6.
    POLYNOMIAL FUNCTIONS EVALUATING APOLYNOMIAL FUNCTION Find f(m + 2) if f(x) = 3x2 – 2x – 6 f(m + 2) = 3(m + 2)2 – 2(m + 2) – 6 f(m + 2) = 3(m2 + 4m + 4) – 2(m + 2) – 6 f(m + 2) = 3m2 + 12m + 12 – 2m – 4 – 6 f(m + 2) = 3m2 + 10m + 2
  • 7.
    POLYNOMIAL FUNCTIONS EVALUATING APOLYNOMIAL FUNCTION Find 2g(-2a) if g(x) = 3x2 – 2x – 6 2g(-2a) = 2[3(-2a)2 – 2(-2a) – 6] 2g(-2a) = 2[12a2 + 4a – 6] 2g(-2a) = 24a2 + 8a – 12
  • 8.
    POLYNOMIAL FUNCTIONS GENERAL SHAPES OF POLYNOMIAL FUNCTIONS f(x) = 3 Constant Function Degree = 0 Max. Zeros: 0
  • 9.
    POLYNOMIAL FUNCTIONS GENERAL SHAPES OF POLYNOMIAL FUNCTIONS f(x) = x + 2 Linear Function Degree = 1 Max. Zeros: 1
  • 10.
    POLYNOMIAL FUNCTIONS GENERAL SHAPES OF POLYNOMIAL FUNCTIONS f(x) = x2 + 3x + 2 Quadratic Function Degree = 2 Max. Zeros: 2
  • 11.
    POLYNOMIAL FUNCTIONS GENERAL SHAPES OF POLYNOMIAL FUNCTIONS f(x) = x3 + 4x2 + 2 Cubic Function Degree = 3 Max. Zeros: 3
  • 12.
    POLYNOMIAL FUNCTIONS GENERAL SHAPES OF POLYNOMIAL FUNCTIONS f(x) = x4 + 4x3 – 2x – 1 Quartic Function Degree = 4 Max. Zeros: 4
  • 13.
    POLYNOMIAL FUNCTIONS GENERAL SHAPES OF POLYNOMIAL FUNCTIONS f(x) = x5 + 4x4 – 2x3 – 4x2 + x – 1 Quintic Function Degree = 5 Max. Zeros: 5
  • 14.
    POLYNOMIAL FUNCTIONS END BEHAVIOR f(x) = x2 Degree: Even Leading Coefficient: + End Behavior: As x  -∞; f(x)  +∞ As x  +∞; f(x)  +∞
  • 15.
    POLYNOMIAL FUNCTIONS END BEHAVIOR f(x) = -x2 Degree: Even Leading Coefficient: – End Behavior: As x  -∞; f(x)  -∞ As x  +∞; f(x)  -∞
  • 16.
    POLYNOMIAL FUNCTIONS END BEHAVIOR f(x) = x3 Degree: Odd Leading Coefficient: + End Behavior: As x  -∞; f(x)  -∞ As x  +∞; f(x)  +∞
  • 17.
    POLYNOMIAL FUNCTIONS END BEHAVIOR f(x) = -x3 Degree: Odd Leading Coefficient: – End Behavior: As x  -∞; f(x)  +∞ As x  +∞; f(x)  -∞
  • 18.
    REMAINDER AND FACTOR THEOREMS f(x) = 2x2 – 3x + 4 Divide the polynomial by x – 2 Find f(2) 2 2 -3 4 f(2) = 2(2)2 – 3(2) + 4 4 2 f(2) = 8 – 6 + 4 2 1 6 f(2) = 6
  • 19.
    REMAINDER AND FACTOR THEOREMS When synthetic division is used to evaluate a function, it is called SYNTHETIC SUBSTITUTION. Try this one: Remember – Some terms are missing f(x) = 3x5 – 4x3 + 5x - 3 Find f(-3)
  • 20.
    REMAINDER AND FACTOR THEOREMS FACTOR THEOREM The binomial x – a is a factor of the polynomial f(x) if and only if f(a) = 0.
  • 21.
    REMAINDER AND FACTOR THEOREMS Is x – 2 a factor of x3 – 3x2 – 4x + 12 2 1 -3 -4 12 -2 -12 Yes, it is a factor, 2 since f(2) = 0. 1 -1 -6 0 Can you find the two remaining factors?
  • 22.
    REMAINDER AND FACTOR THEOREMS (x + 3)( ? )( ? ) = x3 – x2 – 17x - 15 Find the two unknown ( ? ) quantities.