0.3 Polynomials
Chapter 0 Review of Basic Concepts
Concepts & Objectives
⚫ Exponents
⚫ Simplify exponential expressions
⚫ Polynomials
⚫ Add, subtract, multiply, and divide polynomial
expressions
Properties of Exponents
⚫ Recall that for variables x and y and integers a and b:
Multiplying
Dividing
Power to a Power
Distributing a Power
Zero Exponent
+
=a b a b
x x x
−
=
a
a b
b
x
x
x
( ) =
b
a ab
x x
( ) =
a a a
xy x y
=0
1x
Simplifying Exponents
⚫ Example: Simplify
⚫ 1.
⚫ 2.
⚫ 3.
−3 2 2
2 5
25
5
x y z
xy z
( )−
4
2 3
2r s t
( )
4
2 5
3x y−
−
Simplifying Exponents
⚫ Example: Simplify
⚫ 1.
⚫ 2.
⚫ 3.
−3 2 2
2 5
25
5
x y z
xy z
( )−
4
2 3
2r s t
( )
4
2 5
3x y−
−
3 1 2 2 2 525
5
x y z− − − −
=
( ) ( ) ( )4 2 4 3 4 14
2 r s t
−
=
( ) ( ) ( )4 2 4 5 4
3 x y
−
= −
− −
= 2 4 3
5x y z
−
= 8 12 4
16r s t
8 20
81x y−
=
Polynomials
⚫ A polynomial is defined as a term or a finite sum of
terms, with only positive or zero integer exponents
permitted on the variables.
⚫ The degree of a term with one variable is the largest
exponent in the expression. The degree of a term
containing more than one variable has degree equal to
the sum of all of the variables’ exponents.
⚫ The degree of the polynomial is the greatest degree of
any term in the polynomial.
Polynomials (cont.)
⚫ A polynomial containing exactly three term is called a
trinomial. If it contains exactly two terms, it is called a
binomial, and a single-term polynomial is called a
monomial.
⚫ Since the variables used in polynomials represent real
numbers, a polynomial represents a real number. This
means that all of the properties of real numbers hold for
polynomials.
Polynomials (cont.)
⚫ Using the distributive property, we can simplify the
following:
3m5 ‒ 7m5 + 2m2
3 ‒ 7m5 + 2m2
‒4m5 + 2m2
⚫ Thus, polynomials are added/subtracted by adding or
subtracting coefficients of like terms.
⚫ Polynomials in one variable are usually written with
their terms in descending order of degree.
Multiplying Polynomials
⚫ To multiply polynomials, multiply each term by all of the
other terms.
Example: ( )( )
( )( ) ( )( ) ( )( )
( )( ) ( )( ) ( )( )
2
2
2
3 2 2
3 2
2 3 5
2 3 5
2 3 5
6 9 15 8 12 20
6 17 27 20
3
3 3
4
4 4 4
3
x x
x x
x x
x x x x x
x x
x
x
x
x x
− +
= + − +
+ + − +
= − + − + −
−
− +
−
−
−
−
=
Multiplying Polynomials
⚫ You can also use tools such as the “box” method:
2x2 ‒3x 5
3x
‒4
Multiplying Polynomials
⚫ You can also use tools such as the “box” method:
2x2 ‒3x 5
3x 6x3 ‒9x2 15x
‒4
Multiplying Polynomials
⚫ You can also use tools such as the “box” method:
2x2 ‒3x 5
3x 6x3 ‒9x2 15x
‒4 ‒8x2 12x ‒20
Multiplying Polynomials
⚫ You can also use tools such as the “box” method:
Combine like terms:
2x2 ‒3x 5
3x 6x3 ‒9x2 15x
‒4 ‒8x2 12x ‒20
3 2
6 17 27 20x x x− + −
Multiplying Polynomials
⚫ There are a couple of special patterns to be aware of
when multiplying two binomials:
⚫ Product of Sum and Difference/Difference of Squares
⚫ Square of a Binomial
( )( ) 2 2
a b a b a b+ − = −
( ) = +
2 2 2
2a b a ab b
Multiplying Polynomials
Examples: Simplify the following
⚫
⚫
( )( )2 3 2 3x x+ −
( )
2
7 5x −
Multiplying Polynomials
Examples: Simplify the following
⚫
⚫
( )( ) ( )+ − = −
= −
2 2
2
2 3 2 3 2 3
4 9
x x x
x
( ) ( ) ( )( )− = − +
= − +
2 2 2
2
7 5 7 2 7 5 5
49 70 25
x x x
x x
Multiplying Polynomials
EVERY TIME YOU DO THIS:
A KITTEN DIES
( )
2 2 2
x y x y+ = +
Fair Warning!
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
2m‒1  4m3 ‒ 8m2 + 4m + 6
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
2m2
2m‒1  4m3 ‒ 8m2 + 4m + 6
4m3 – 2m2
You have to cancel
out the first term,
so this has to be
the same.
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
2m2
2m‒1  4m3 ‒ 8m2 + 4m + 6
4m3 + 2m2
‒6m2 + 4m
–Now change all of
the signs.
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
2m2 ‒ 3m
2m‒1  4m3 ‒ 8m2 + 4m + 6
4m3 + 2m2
‒6m2 + 4m
–6m2 + 3m
–
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
2m2 ‒ 3m
2m‒1  4m3 ‒ 8m2 + 4m + 6
4m3 + 2m2
‒6m2 + 4m
+6m2 – 3m
m + 6
–
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
2m2 ‒ 3m + ½
2m‒1  4m3 ‒ 8m2 + 4m + 6
4m3 + 2m2
‒6m2 + 4m
+6m2 – 3m
m + 6
m – ½
–
Dividing Polynomials
⚫ To divide polynomials, we use much the same process
we use to divide whole numbers:
Example: Divide 3 2
4 8 4 6 by 2 1m m m m− + + −
2m2 ‒ 3m + ½
2m‒1  4m3 ‒ 8m2 + 4m + 6
4m3 + 2m2
‒6m2 + 4m
+6m2 – 3m
m + 6
m + ½
13
2
–
–
12
6
2
 
= 
 
Dividing Polynomials
⚫ Therefore,
⚫ If either polynomial does not have a term for each
power, you will need to insert a placeholder for it.
3 2
2
13
4 8 4 6 1 22 3
2 1 2 2 1
m m m
m m
m m
− + +
= − + +
− −
Dividing Polynomials
⚫ Example: Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4
x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150
Dividing Polynomials
⚫ Example: Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4
3x
x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150
3x3 + 0x2 ‒ 12x
‒ 2x2 + 12x ‒ 150
Dividing Polynomials
⚫ Example: Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4
3x ‒ 2
x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150
3x3 + 0x2 ‒ 12x
‒ 2x2 + 12x ‒ 150
‒ 2x2 + 0x + 8
12x ‒ 158
Dividing Polynomials
⚫ Example: Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4
So,
3x ‒ 2
x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150
3x3 + 0x2 ‒ 12x
‒ 2x2 + 12x ‒ 150
‒ 2x2 + 0x + 8
12x ‒ 158
3 2
2 2
3 2 150 12 158
3 2
4 4
x x x
x
x x
− − −
= − +
− −
Classwork
⚫ College Algebra
⚫ 0.3 Assignment – page 30: 12-28, page 19: 44-64 (x4),
page 7: 66-90
⚫ 0.3 Classwork Check
⚫ Quiz 0.2

0.3 Polynomials

  • 1.
    0.3 Polynomials Chapter 0Review of Basic Concepts
  • 2.
    Concepts & Objectives ⚫Exponents ⚫ Simplify exponential expressions ⚫ Polynomials ⚫ Add, subtract, multiply, and divide polynomial expressions
  • 3.
    Properties of Exponents ⚫Recall that for variables x and y and integers a and b: Multiplying Dividing Power to a Power Distributing a Power Zero Exponent + =a b a b x x x − = a a b b x x x ( ) = b a ab x x ( ) = a a a xy x y =0 1x
  • 4.
    Simplifying Exponents ⚫ Example:Simplify ⚫ 1. ⚫ 2. ⚫ 3. −3 2 2 2 5 25 5 x y z xy z ( )− 4 2 3 2r s t ( ) 4 2 5 3x y− −
  • 5.
    Simplifying Exponents ⚫ Example:Simplify ⚫ 1. ⚫ 2. ⚫ 3. −3 2 2 2 5 25 5 x y z xy z ( )− 4 2 3 2r s t ( ) 4 2 5 3x y− − 3 1 2 2 2 525 5 x y z− − − − = ( ) ( ) ( )4 2 4 3 4 14 2 r s t − = ( ) ( ) ( )4 2 4 5 4 3 x y − = − − − = 2 4 3 5x y z − = 8 12 4 16r s t 8 20 81x y− =
  • 6.
    Polynomials ⚫ A polynomialis defined as a term or a finite sum of terms, with only positive or zero integer exponents permitted on the variables. ⚫ The degree of a term with one variable is the largest exponent in the expression. The degree of a term containing more than one variable has degree equal to the sum of all of the variables’ exponents. ⚫ The degree of the polynomial is the greatest degree of any term in the polynomial.
  • 7.
    Polynomials (cont.) ⚫ Apolynomial containing exactly three term is called a trinomial. If it contains exactly two terms, it is called a binomial, and a single-term polynomial is called a monomial. ⚫ Since the variables used in polynomials represent real numbers, a polynomial represents a real number. This means that all of the properties of real numbers hold for polynomials.
  • 8.
    Polynomials (cont.) ⚫ Usingthe distributive property, we can simplify the following: 3m5 ‒ 7m5 + 2m2 3 ‒ 7m5 + 2m2 ‒4m5 + 2m2 ⚫ Thus, polynomials are added/subtracted by adding or subtracting coefficients of like terms. ⚫ Polynomials in one variable are usually written with their terms in descending order of degree.
  • 9.
    Multiplying Polynomials ⚫ Tomultiply polynomials, multiply each term by all of the other terms. Example: ( )( ) ( )( ) ( )( ) ( )( ) ( )( ) ( )( ) ( )( ) 2 2 2 3 2 2 3 2 2 3 5 2 3 5 2 3 5 6 9 15 8 12 20 6 17 27 20 3 3 3 4 4 4 4 3 x x x x x x x x x x x x x x x x x x − + = + − + + + − + = − + − + − − − + − − − − =
  • 10.
    Multiplying Polynomials ⚫ Youcan also use tools such as the “box” method: 2x2 ‒3x 5 3x ‒4
  • 11.
    Multiplying Polynomials ⚫ Youcan also use tools such as the “box” method: 2x2 ‒3x 5 3x 6x3 ‒9x2 15x ‒4
  • 12.
    Multiplying Polynomials ⚫ Youcan also use tools such as the “box” method: 2x2 ‒3x 5 3x 6x3 ‒9x2 15x ‒4 ‒8x2 12x ‒20
  • 13.
    Multiplying Polynomials ⚫ Youcan also use tools such as the “box” method: Combine like terms: 2x2 ‒3x 5 3x 6x3 ‒9x2 15x ‒4 ‒8x2 12x ‒20 3 2 6 17 27 20x x x− + −
  • 14.
    Multiplying Polynomials ⚫ Thereare a couple of special patterns to be aware of when multiplying two binomials: ⚫ Product of Sum and Difference/Difference of Squares ⚫ Square of a Binomial ( )( ) 2 2 a b a b a b+ − = − ( ) = + 2 2 2 2a b a ab b
  • 15.
    Multiplying Polynomials Examples: Simplifythe following ⚫ ⚫ ( )( )2 3 2 3x x+ − ( ) 2 7 5x −
  • 16.
    Multiplying Polynomials Examples: Simplifythe following ⚫ ⚫ ( )( ) ( )+ − = − = − 2 2 2 2 3 2 3 2 3 4 9 x x x x ( ) ( ) ( )( )− = − + = − + 2 2 2 2 7 5 7 2 7 5 5 49 70 25 x x x x x
  • 17.
    Multiplying Polynomials EVERY TIMEYOU DO THIS: A KITTEN DIES ( ) 2 2 2 x y x y+ = + Fair Warning!
  • 18.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + −
  • 19.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + − 2m‒1  4m3 ‒ 8m2 + 4m + 6
  • 20.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + − 2m2 2m‒1  4m3 ‒ 8m2 + 4m + 6 4m3 – 2m2 You have to cancel out the first term, so this has to be the same.
  • 21.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + − 2m2 2m‒1  4m3 ‒ 8m2 + 4m + 6 4m3 + 2m2 ‒6m2 + 4m –Now change all of the signs.
  • 22.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + − 2m2 ‒ 3m 2m‒1  4m3 ‒ 8m2 + 4m + 6 4m3 + 2m2 ‒6m2 + 4m –6m2 + 3m –
  • 23.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + − 2m2 ‒ 3m 2m‒1  4m3 ‒ 8m2 + 4m + 6 4m3 + 2m2 ‒6m2 + 4m +6m2 – 3m m + 6 –
  • 24.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + − 2m2 ‒ 3m + ½ 2m‒1  4m3 ‒ 8m2 + 4m + 6 4m3 + 2m2 ‒6m2 + 4m +6m2 – 3m m + 6 m – ½ –
  • 25.
    Dividing Polynomials ⚫ Todivide polynomials, we use much the same process we use to divide whole numbers: Example: Divide 3 2 4 8 4 6 by 2 1m m m m− + + − 2m2 ‒ 3m + ½ 2m‒1  4m3 ‒ 8m2 + 4m + 6 4m3 + 2m2 ‒6m2 + 4m +6m2 – 3m m + 6 m + ½ 13 2 – – 12 6 2   =   
  • 26.
    Dividing Polynomials ⚫ Therefore, ⚫If either polynomial does not have a term for each power, you will need to insert a placeholder for it. 3 2 2 13 4 8 4 6 1 22 3 2 1 2 2 1 m m m m m m m − + + = − + + − −
  • 27.
    Dividing Polynomials ⚫ Example:Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4 x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150
  • 28.
    Dividing Polynomials ⚫ Example:Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4 3x x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150 3x3 + 0x2 ‒ 12x ‒ 2x2 + 12x ‒ 150
  • 29.
    Dividing Polynomials ⚫ Example:Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4 3x ‒ 2 x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150 3x3 + 0x2 ‒ 12x ‒ 2x2 + 12x ‒ 150 ‒ 2x2 + 0x + 8 12x ‒ 158
  • 30.
    Dividing Polynomials ⚫ Example:Divide 3x3 ‒ 2x2 ‒ 150 by x2 ‒ 4 So, 3x ‒ 2 x2 + 0x ‒ 4  3x3 ‒ 2x2 + 0x ‒ 150 3x3 + 0x2 ‒ 12x ‒ 2x2 + 12x ‒ 150 ‒ 2x2 + 0x + 8 12x ‒ 158 3 2 2 2 3 2 150 12 158 3 2 4 4 x x x x x x − − − = − + − −
  • 31.
    Classwork ⚫ College Algebra ⚫0.3 Assignment – page 30: 12-28, page 19: 44-64 (x4), page 7: 66-90 ⚫ 0.3 Classwork Check ⚫ Quiz 0.2