1.2 Exponents and Scientific
Notation
Chapter 1 Prerequisites
Concepts & Objectives
⚫ Objectives for this section:
⚫ Use exponent rules.
⚫ Find the power of a product and a quotient.
⚫ Simplify exponential expressions.
⚫ Use scientific notation.
Properties of Exponents
⚫ Recall that for variables x and y and integers a and b:
Product Rule
Quotient Rule
Power Rule
Zero Exponent
Negative Rule
+
=
a b a b
x x x
−
=
a
a b
b
x
x
x
( ) =
b
a ab
x x
−
=
1
a
a
x
x
=
0
1
x
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 5
25
5
x y z
− − − −
=
( ) ( ) ( )
4 2 4 3 4 1
4
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
−
=
Scientific Notation
⚫ A shorthand method of writing very small and very large
numbers is called scientific notation, in which we express
numbers in terms of exponents of 10.
⚫ To write a number in scientific notation
⚫ Move the decimal point to the right of the first nonzero digit in
the number.
⚫ Write the digits as a decimal number between 1 and 10.
⚫ Count the number of places n that you moved the decimal point.
⚫ Multiply the decimal number by 10 raised to a power of n. If you
moved the decimal left (large number), n is positive; if you
moved it right (small number), n is negative.
Scientific Notation (cont.)
Example: Write 2,780,000 in scientific notation.
Scientific Notation (cont.)
Example: Write 2,780,000 in scientific notation.
⚫ Moving the decimal 6 places to the left means n = 6,
therefore our answer is
⚫ Notice that we can drop the extra zeros.
6 places to
the left
 6
2.78 10
Scientific Notation (cont.)
Example: Write 0.00000000000047 in scientific notation.
Scientific Notation (cont.)
Example: Write 0.00000000000047 in scientific notation.
⚫ Moving the decimal 13 places to the right means n = ‒13,
therefore our answer is
13 places
to the left
13
4.7 10−

Scientific Notation (cont.)
⚫ To convert a number in scientific notation to standard
notation, simply reverse the process.
⚫ Move the decimal n places to the right if n is positive
or n places to the left if n is negative.
⚫ Add zeros as needed.
⚫ Remember, if n is positive, the absolute value of the
number is greater than 1, and if n is negative, the
absolute value of the number is less than 1.
Scientific Notation (cont.)
Example: Convert 3.547×1014 to standard notation.
Shift the decimal point 14 places to the right and fill
in the blanks with 0s.
354700000000000 or 354,700,000,000,000
Scientific Notation (cont.)
Example: Convert 7.91×10‒7 to standard notation.
Shift the decimal point 7 places to the left and fill in
the blanks with 0s.
.000000791 or 0.000000791
Classwork
College Algebra 2e (OpenStax.org)
⚫ 1.2: 6-24 (even); 1.1: 28-56 (×4)
⚫ 1.2 Classwork Check (in Canvas)
⚫ Quiz 1.1

1.2 Exponents and Scientific Notation

  • 1.
    1.2 Exponents andScientific Notation Chapter 1 Prerequisites
  • 2.
    Concepts & Objectives ⚫Objectives for this section: ⚫ Use exponent rules. ⚫ Find the power of a product and a quotient. ⚫ Simplify exponential expressions. ⚫ Use scientific notation.
  • 3.
    Properties of Exponents ⚫Recall that for variables x and y and integers a and b: Product Rule Quotient Rule Power Rule Zero Exponent Negative Rule + = a b a b x x x − = a a b b x x x ( ) = b a ab x x − = 1 a a x x = 0 1 x
  • 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 5 25 5 x y z − − − − = ( ) ( ) ( ) 4 2 4 3 4 1 4 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.
    Scientific Notation ⚫ Ashorthand method of writing very small and very large numbers is called scientific notation, in which we express numbers in terms of exponents of 10. ⚫ To write a number in scientific notation ⚫ Move the decimal point to the right of the first nonzero digit in the number. ⚫ Write the digits as a decimal number between 1 and 10. ⚫ Count the number of places n that you moved the decimal point. ⚫ Multiply the decimal number by 10 raised to a power of n. If you moved the decimal left (large number), n is positive; if you moved it right (small number), n is negative.
  • 7.
    Scientific Notation (cont.) Example:Write 2,780,000 in scientific notation.
  • 8.
    Scientific Notation (cont.) Example:Write 2,780,000 in scientific notation. ⚫ Moving the decimal 6 places to the left means n = 6, therefore our answer is ⚫ Notice that we can drop the extra zeros. 6 places to the left  6 2.78 10
  • 9.
    Scientific Notation (cont.) Example:Write 0.00000000000047 in scientific notation.
  • 10.
    Scientific Notation (cont.) Example:Write 0.00000000000047 in scientific notation. ⚫ Moving the decimal 13 places to the right means n = ‒13, therefore our answer is 13 places to the left 13 4.7 10− 
  • 11.
    Scientific Notation (cont.) ⚫To convert a number in scientific notation to standard notation, simply reverse the process. ⚫ Move the decimal n places to the right if n is positive or n places to the left if n is negative. ⚫ Add zeros as needed. ⚫ Remember, if n is positive, the absolute value of the number is greater than 1, and if n is negative, the absolute value of the number is less than 1.
  • 12.
    Scientific Notation (cont.) Example:Convert 3.547×1014 to standard notation. Shift the decimal point 14 places to the right and fill in the blanks with 0s. 354700000000000 or 354,700,000,000,000
  • 13.
    Scientific Notation (cont.) Example:Convert 7.91×10‒7 to standard notation. Shift the decimal point 7 places to the left and fill in the blanks with 0s. .000000791 or 0.000000791
  • 14.
    Classwork College Algebra 2e(OpenStax.org) ⚫ 1.2: 6-24 (even); 1.1: 28-56 (×4) ⚫ 1.2 Classwork Check (in Canvas) ⚫ Quiz 1.1