68 CHAPTER 1 The Real Number System
Number Additive Inverse Multiplicative Inverse
5x- y 1 yZ 02
1 xZ 023
8-^12
- 10
In general, a number and its addi-
tive inverse have signs.
(the same/opposite)
A number and its multiplicative
inverse have signs.
(the same/opposite)22.Concept Check The following conversation actually took place between one of the
authors of this book and his son, Jack, when Jack was 4 years old:
DADDY: “Jack, what is ”
JACK: “3.”
DADDY: “Jack, what is ”
JACK: “4. And Daddy, stringplus zero equals string!”
What property of addition did Jack recognize?Decide whether each statement is an example of thecommutative, associative, identity,
inverse,ordistributive property.See Examples 1, 2, 3, 5, 6, 7, and 9.Find each sum or product. See Example 4.Simplify each expression. See Examples 7 and 8.58. 59. 60.
- 62.w+ 1 - w 2 +
1
4
t+ 1 - t 2 + 1421
2
122
a4
5
b1-0.732a5
4
a b9
7
b1-0.382a7
9
b1
5
y+ 4 - 4 -1
5
y2
3
x- 11 + 11 -2
3
6 t+ 8 - 6 t+ 3 9 r+ 12 - 9 r+ 1 x- 4 # 5 # 93 # 5 2 # 25 # 67 # 1 - 22
51472122 217925
843 + 627 + 1 - 432 + 1 - 272 1846 + 1293 + 1 - 462 + 1 - 932
159 + 12 + 141 + 88 106 + 8 + 1 - 62 + 1 - 82
1999 + 2 + 1 + 8 2998 + 3 + 2 + 17
97 + 13 + 3 + 37 49 + 199 + 1 + 1
412 x 2 + 413 y 2 = 412 x+ 3 y 2 615 t 2 - 617 r 2 = 615 t- 7 r 2-
7
12
=-
7
12
#^7
7=-
49
84
-
5
9
=-
5
9
#^3
3=-
15
27
21 x+y 2 = 2 x+ 2 y 91 t+s 2 = 9 t+ 9 s14 + 172 + 3 = 3 + 14 + 172 1 - 8 + 42 + 12 = 12 + 1 - 8 + 42
1.75+ 0 =1.75 -8.45+ 0 =-8.45
5
8
a8
5
b= 12
3
a3
2
b= 1- 9 + 9 = 0 1 + 1 - 12 = 0
- 6 + 112 + 72 = 1 - 6 + 122 + 7 1 - 8 + 132 + 2 =- 8 + 113 + 22
5 # 113 # 72 = 15 # 132 # 7 - 4 # 12 # 62 = 1 - 4 # 22 # 6
4 + 15 = 15 + 4 3 + 12 = 12 + 3
4 +0?
3 +0?
21.Concept Check Complete the table and the statement beside it.http://www.ebook777.com
http://www.ebook777.com