(f )
Apply the exponents.
Divide.
Multiply.
Add.
= 113 Subtract.
= 140 - 27
= 108 + 32 - 27
= 36 # 3 + 4 # 8 - 27
= 72 , 2 # 3 + 4 # 8 - 27
72 , 2 # 3 + 4 # 23 - 33
SECTION 1.2 Exponents, Order of Operations, and Inequality 17
NOW TRY
EXERCISE 2
Find the value of each
expression.
(a)
(b)
(c) 8 # 10 , 4 - 23 + 3 # 42
612 + 42 - 7 # 5
15 - 2 # 6
Think: 3^3 = 3 # 3 # 3
⎧⎨⎩
⎧⎨⎩ ⎧⎨⎩
Multiplications and divisions are done from left to right as they appear. Then
additions and subtractions are done from left to right as they appear. NOW TRY
OBJECTIVE 3 Use more than one grouping symbol. In an expression such as
we often use brackets, in place of one pair of parentheses.
Using Brackets and Fraction Bars as Grouping Symbols
Simplify each expression.
(a)
Add inside parentheses.
Multiply inside brackets.
Add inside brackets.
= 82 Multiply.
= 23414
= 238 + 334
= 238 + 311124
238 + 316 + 524
EXAMPLE 3
218 + 316 + 522 , 34 ,
NOW TRY
EXERCISE 3
Simplify each expression.
(a)
(b)
9114 - 42 - 2
4 + 3 # 6
73132 - 12 + 44
NOW TRY ANSWERS
- (a) 3 (b) 1 (c) 60
- (a) 84 (b) 4
(b) Simplify the numerator and denominator separately.
Work inside parentheses.
Multiply.
= or 7 Add and subtract. Then divide. NOW TRY
35
5
,
=
32 + 3
6 - 1
=
4182 + 3
2132 - 1
415 + 32 + 3
2132 - 1
NOTE The expression in Example 3(b)can be written as the quotient
which shows that the fraction bar “groups” the numerator and denominator separately.
3415 + 32 + 34 , 32132 - 14 ,
415 + 32 + 3
2132 - 1
OBJECTIVE 4 Know the meanings of , <, >, , and. So far, we have
used the equality symbol The symbols and are used to express an
inequality,a statement that two expressions may not be equal. The equality symbol
with a slash through it, means “is not equal to.”
7 is not equal to 8.