3. Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
4. Terms with the same variabe part are called like-terms.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
5. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
6. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
7. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
8. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
9. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
In particular x2 + x2 = 2x2 = x4,
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
10. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
In particular x2 + x2 = 2x2 = x4, and that x2 + x3 = x2 + x3 = x5.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
11. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
In particular x2 + x2 = 2x2 = x4, and that x2 + x3 = x2 + x3 = x5.
Note that we write 1xN as xN , –1xN as –xN.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
12. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
In particular x2 + x2 = 2x2 = x4, and that x2 + x3 = x2 + x3 = x5.
Note that we write 1xN as xN , –1xN as –xN.
When multiplying a number with a term, we multiply it to the
coefficient.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
13. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
In particular x2 + x2 = 2x2 = x4, and that x2 + x3 = x2 + x3 = x5.
Note that we write 1xN as xN , –1xN as –xN.
When multiplying a number with a term, we multiply it to the
coefficient. Hence, 3(5x) = (3*5)x =15x,
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
14. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
In particular x2 + x2 = 2x2 = x4, and that x2 + x3 = x2 + x3 = x5.
Note that we write 1xN as xN , –1xN as –xN.
When multiplying a number with a term, we multiply it to the
coefficient. Hence, 3(5x) = (3*5)x =15x,
and –2(–4x) = (–2)(–4)x = 8x.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
15. Terms with the same variabe part are called like-terms.
Like-terms may be combined.
For example, 4x + 5x – 3x2 – 5x2 = 9x – 2x2.
Unlike terms may not be combined.
In particular x2 + x2 = 2x2 = x4, and that x2 + x3 = x2 + x3 = x5.
Note that we write 1xN as xN , –1xN as –xN.
When multiplying a number with a term, we multiply it to the
coefficient. Hence, 3(5x) = (3*5)x =15x,
and –2(–4x) = (–2)(–4)x = 8x.
When multiplying a number to a polynomial, we may expand
the result using the distributive law: A(B ± C) = AB ± AC.
Polynomial Operations
In the last section, we introduced polynomial expressions.
Given a polynomial, each monomial is called a term.
#xN ± #xN-1 ± … ± #x ± #
terms
25. Example A. Expand and simplify.
a. 3(2x – 4) + 2(4 – 5x)
= 6x – 12 + 8 – 10x
= –4x – 4
b. –3(x2 – 3x + 5) – 2(–x2 – 4x – 6)
= –3x2 + 9x – 15 + 2x2 + 8x +12
= –x2 + 17x – 3
Polynomial Operations
When multiply a term with another term, we multiply the
coefficient with the coefficient and the variable with the
variable.
26. Example A. Expand and simplify.
a. 3(2x – 4) + 2(4 – 5x)
= 6x – 12 + 8 – 10x
= –4x – 4
b. –3(x2 – 3x + 5) – 2(–x2 – 4x – 6)
= –3x2 + 9x – 15 + 2x2 + 8x +12
= –x2 + 17x – 3
Polynomial Operations
When multiply a term with another term, we multiply the
coefficient with the coefficient and the variable with the
variable.
Example B.
a. (3x2)(2x3) =
b. 3x2(–4x) =
c. 3x2(2x3 – 4x)
=
27. Example A. Expand and simplify.
a. 3(2x – 4) + 2(4 – 5x)
= 6x – 12 + 8 – 10x
= –4x – 4
b. –3(x2 – 3x + 5) – 2(–x2 – 4x – 6)
= –3x2 + 9x – 15 + 2x2 + 8x +12
= –x2 + 17x – 3
Polynomial Operations
When multiply a term with another term, we multiply the
coefficient with the coefficient and the variable with the
variable.
Example B.
a. (3x2)(2x3) = 3*2x2x3
b. 3x2(–4x) =
c. 3x2(2x3 – 4x)
=
28. Example A. Expand and simplify.
a. 3(2x – 4) + 2(4 – 5x)
= 6x – 12 + 8 – 10x
= –4x – 4
b. –3(x2 – 3x + 5) – 2(–x2 – 4x – 6)
= –3x2 + 9x – 15 + 2x2 + 8x +12
= –x2 + 17x – 3
Polynomial Operations
When multiply a term with another term, we multiply the
coefficient with the coefficient and the variable with the
variable.
Example B.
a. (3x2)(2x3) = 3*2x2x3 = 6x5
b. 3x2(–4x) =
c. 3x2(2x3 – 4x)
=
29. Example A. Expand and simplify.
a. 3(2x – 4) + 2(4 – 5x)
= 6x – 12 + 8 – 10x
= –4x – 4
b. –3(x2 – 3x + 5) – 2(–x2 – 4x – 6)
= –3x2 + 9x – 15 + 2x2 + 8x +12
= –x2 + 17x – 3
Polynomial Operations
When multiply a term with another term, we multiply the
coefficient with the coefficient and the variable with the
variable.
Example B.
a. (3x2)(2x3) = 3*2x2x3 = 6x5
b. 3x2(–4x) = 3(–4)x2x = –12x3
c. 3x2(2x3 – 4x)
=
30. Example A. Expand and simplify.
a. 3(2x – 4) + 2(4 – 5x)
= 6x – 12 + 8 – 10x
= –4x – 4
b. –3(x2 – 3x + 5) – 2(–x2 – 4x – 6)
= –3x2 + 9x – 15 + 2x2 + 8x +12
= –x2 + 17x – 3
Polynomial Operations
When multiply a term with another term, we multiply the
coefficient with the coefficient and the variable with the
variable.
Example B.
a. (3x2)(2x3) = 3*2x2x3 = 6x5
b. 3x2(–4x) = 3(–4)x2x = –12x3
c. 3x2(2x3 – 4x) distribute
= 6x5 – 12x3
31. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
32. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
a. (3x + 2)(2x – 1)
33. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
= 3x(2x – 1) + 2(2x – 1)
a. (3x + 2)(2x – 1)
34. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
a. (3x + 2)(2x – 1)
35. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
a. (3x + 2)(2x – 1)
36. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
b. (2x – 1)(2x2 + 3x –4)
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
a. (3x + 2)(2x – 1)
37. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
b. (2x – 1)(2x2 + 3x –4)
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
= 2x(2x2 + 3x –4) –1(2x2 + 3x – 4)
a. (3x + 2)(2x – 1)
38. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
b. (2x – 1)(2x2 + 3x –4)
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
= 2x(2x2 + 3x –4) –1(2x2 + 3x – 4)
= 4x3 + 6x2 – 8x – 2x2 – 3x + 4
a. (3x + 2)(2x – 1)
39. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
b. (2x – 1)(2x2 + 3x –4)
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
= 2x(2x2 + 3x –4) –1(2x2 + 3x – 4)
= 4x3 + 6x2 – 8x – 2x2 – 3x + 4
= 4x3 + 4x2 – 11x + 4
a. (3x + 2)(2x – 1)
40. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
b. (2x – 1)(2x2 + 3x –4)
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
= 2x(2x2 + 3x –4) –1(2x2 + 3x – 4)
= 4x3 + 6x2 – 8x – 2x2 – 3x + 4
= 4x3 + 4x2 – 11x + 4
a. (3x + 2)(2x – 1)
Note that if we did (2x – 1)(3x + 2) or (2x2 + 3x –4)(2x – 1)
instead, we get the same answers. (Check this.)
41. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
b. (2x – 1)(2x2 + 3x –4)
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
= 2x(2x2 + 3x –4) –1(2x2 + 3x – 4)
= 4x3 + 6x2 – 8x – 2x2 – 3x + 4
= 4x3 + 4x2 – 11x + 4
a. (3x + 2)(2x – 1)
Note that if we did (2x – 1)(3x + 2) or (2x2 + 3x –4)(2x – 1)
instead, we get the same answers. (Check this.)
Fact. If P and Q are two polynomials then PQ ≡ QP.
42. To multiply two polynomials, we may multiply each term of one
polynomial against other polynomial then expand and simplify.
Polynomial Operations
Example C.
b. (2x – 1)(2x2 + 3x –4)
= 3x(2x – 1) + 2(2x – 1)
= 6x2 – 3x + 4x – 2
= 6x2 + x – 2
= 2x(2x2 + 3x –4) –1(2x2 + 3x – 4)
= 4x3 + 6x2 – 8x – 2x2 – 3x + 4
= 4x3 + 4x2 – 11x + 4
a. (3x + 2)(2x – 1)
Note that if we did (2x – 1)(3x + 2) or (2x2 + 3x –4)(2x – 1)
instead, we get the same answers. (Check this.)
Fact. If P and Q are two polynomials then PQ ≡ QP.
A shorter way to multiply is to bypass the 2nd step and use the
general distributive law.
47. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Polynomial Operations
48. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
Polynomial Operations
49. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2
Polynomial Operations
50. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x
Polynomial Operations
51. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x
Polynomial Operations
52. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12
Polynomial Operations
53. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
Polynomial Operations
54. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
55. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3
56. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3 – 2x2
57. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3 – 2x2 – 2x
58. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3 – 2x2 – 2x – 3x2
59. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3 – 2x2 – 2x – 3x2 + 6x
60. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3 – 2x2 – 2x – 3x2 + 6x + 6
61. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3 – 2x2 – 2x – 3x2 + 6x + 6
= x3– 5x2 + 4x + 6
We will address the division operation of polynomials later-
after we understand more about the multiplication operation.
62. General Distributive Rule:
(A ± B ± C ± ..)(a ± b ± c ..)
= Aa ± Ab ± Ac ..± Ba ± Bb ± Bc ..±Ca ± Cb ± Cc ..
Example D. Expand
a. (x + 3)(x – 4)
= x2 – 4x + 3x – 12 simplify
= x2 – x – 12
b. (x – 3)(x2 – 2x – 2)
Polynomial Operations
= x3 – 2x2 – 2x – 3x2 + 6x + 6
= x3– 5x2 + 4x + 6
We will address the division operation of polynomials later-
after we understand more about the multiplication operation.
63. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3
x3
64. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Next collect all the x2 terms in the product,
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3
65. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Next collect all the x2 terms in the product, they are
–3*x2
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3
–3x2
66. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Next collect all the x2 terms in the product, they are
–3*x2 and x*(–2x)
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3
–3x2
–2x2
67. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Next collect all the x2 terms in the product, they are
–3*x2 and x*(–2x) which gives –3x2 – 2x2 = – 5x2.
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3 – 5x2
–3x2
–2x2
68. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Next collect all the x2 terms in the product, they are
–3*x2 and x*(–2x) which gives –3x2 – 2x2 = – 5x2.
Next collect the x–terms
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3 – 5x2
69. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Next collect all the x2 terms in the product, they are
–3*x2 and x*(–2x) which gives –3x2 – 2x2 = – 5x2.
Next collect the x–terms and they are x*(–2) + –3*(–2x) = 4x.
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3 – 5x2 + 4x
–2x
6x
70. We include the following method for multiplying polynomials.
Instead of expand all the terms then collect like–terms, we
scan the like–terms and collect them starting from the highest
degree term in the answer. We demonstrate this method and
double check the answer in part b.
Example E. Multiply
a. (x – 3)(x2 – 2x – 2)
The highest degree term in the product is the x3 term so we
start with the x3–term. It’s x*x2 = 1x3.
Next collect all the x2 terms in the product, they are
–3*x2 and x*(–2x) which gives –3x2 – 2x2 = – 5x2.
Next collect the x–terms and they are x*(–2) + –3*(–2x) = 4x.
The last term is the number term or –3(–2) = 6.
Polynomial Operations
(x – 3)(x2 – 2x – 2) = x3 – 5x2 + 4x + 6 (same as before)
6