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Unit 14 CCM6+/7+ Page 1
Page 1
UNIT 14
Exponents
and
Scientific Notation
CCM6+/7+
Name_________________________________
Math Teacher___________________________
Projected Test Date___________
Main Ideas Page(s) Unit 14 Vocabulary 2
Exponent Basics, Zero & Negative Exponents 3 – 6
Multiplying, Dividing, and Raising a Power to a Power 7 – 13
Laws of Exponents Review 14 – 15
Intro to Scientific Notation 16 – 19
Operations with Scientific Notation 20 – 22
Real World Scientific Notation Problems 23 – 24
Study Guide 25 – 28
Unit 14 CCM6+/7+ Page 2
Page 2
CCM6+/7+ Plus Unit 14: Exponents and Scientific Notation
Base When a number is raised to a power, the number that is used as a factor.
Dividing Powers with
the Same Base Property For every nonzero number a and integers m and n,
Exponent The number that indicates how many times the base is used as a factor.
Exponential Form A number is written in exponential form when it has a base and an exponent.
Irrational Numbers A number that cannot be expressed as a ratio of two integers (or as a repeating or
terminating decimal)
Laws of Exponents The "Laws of Exponents" (also called "Rules of Exponents") come from three
ideas: The exponent says how many times to use the number in a multiplication.
Multiplication Property
of Exponents
For any nonzero number a and integers m and n, am•an=am+n
Perfect Cube The cube of a rational number
Perfect Square The square of a rational number
Power The power of a number says how many times to use the number in a
multiplication.
Raising a Power to a
Power Property
For every nonzero number a and integers m and n, (am)n=amn
Raising a Product to a
Power Property
For every nonzero number a and b integer n, (ab)n=anbn
Raising a Quotient to a
Power Property For every nonzero numbers a and b and integer n,
Rational Numbers A number expressible in the form of a/b or -a/b for some fraction a/b. Rational
numbers include integers
Scientific Notation
A method of writing very large or very small numbers by using a number written
between 1 and 10 multiplied by a power of 10. A number written as the product of
two factors in the form , where n is an integer and
Standard Form of a
Number
Standard form is a way of writing down very large or very small numbers easily
Zero Exponent For every non-zero number a, a0 = 1.
Unit 14 CCM6+/7+ Page 3
Page 3
Exponential Form and Properties of Exponents
Vocabulary Labeled Example
Base
Exponent
Write each of these expressions in exponential form.
a. (−6) ∙ (−6) ∙ (−6) ∙ (−6) ∙ (−6) b. 𝑥 ∙ 𝑥 ∙ 𝑥 ∙ 𝑥 ∙ 𝑥 ∙ 𝑥 ∙ 𝑥 ∙ 𝑥 ∙ 𝑥
c. 8888888888
1
d.
77777
44444444
Unit 14 CCM6+/7+ Page 4
Page 4
Zero Property of Exponents and Negative Exponents
The exponent pattern: 24 = 2•2•2•2 = _______
23 = 2•2•2 = _______
22 = 2•2 = _______
21 = _______
20 = _____________ = ________
2-1 = ____________ = ________
2-2 = ____________ = ________
What happens to the product when you increase the exponent by one?
What happens to the product when you decrease the exponent by one?
Predict the answer for 20, 2-1, and 2-2. Be sure to follow your “rule!” When finished, discuss
your ideas with a partner.
Let’s try a different base: 54 = 5•5•5•5 = _______
53 = 5•5•5 = _______
52 = 5•5 = _______
51 = _______
50 = _______
5-1 = _______
5-2 = _______
5-3 = _______
Unit 14 CCM6+/7+ Page 5
Page 5
Zero Property of Exponents and Negative Exponents
For every nonzero number x, x0 = ____
For every nonzero number x, x-a = _____ Examples. Simplify each expression completely.
1. 40 2. (-7.8)0 3. b-5
4. 6-3 5. 9
1
b 6.
2
1
3
7. 3
6
a
m 8.
3
6
a
m
9.
6 3
1
m a
Zero and Negative Exponents
Simplify each expression
1) 4x0•50
2) 3-2
3) 2-4•2-8
4) (1
5)-3
5) -3a-2b-4 6) 5x0p-3
Rules
Unit 14 CCM6+/7+ Page 6
Page 6
0 0 2 4
6
-3
2 0
1) Simplify:
a) 6 b) 4 c) 5
2 1 d) e)
3 4
2) Evaluate when 2, 1, 3
a) 4
x y x
x
a b c
a b
-3
23 -2
-1
b) 5a
6c c) d) 2 b
ba
3) Simplify an • a-n. What is the mathematical relationship of
an and a-n? Justify your answer.
4) Are 3x-2 and 3x2 reciprocals? Explain.
5) Choose a fraction to use as a value for the variable a. Find the
values of a-1, a2, and a-2.
Unit 14 CCM6+/7+ Page 7
Page 7
Multiplication Property of Exponents
Ex. 4 56 6 = _______________________ =
6
Ex. 5e e = _______________________ =
e
Ex. 6 7 125f f f = _______________________ =
f
To multiply numbers or variables that are raised to a power, __________ the
exponents of the numbers or variables with the __________________________.
Examples. Simplify each expression completely.
1. 3 33 2. m5 m7 m87 3. a5
a b2 a11
4. x2y4x3y 5. (32)(3)(23) 6. c4 d7 c17
What do you do when there are coefficients?
Example: 6a33a 2a5
1. 6y2 3y3 2y4
2. 2y3 7x2 2y4
3. 5m 2p4 3m8
Rule
Unit 14 CCM6+/7+ Page 8
Page 8
Multiplication with Exponents
2 3 ?
?
5 5 (5 5) (5 5 5) 5
Rule: a bx x x
6 7
Example 1: Rewrite using one base.
4 4
4 2
3 5
-2 4 6 3
2 3 5 7
Example 2: Simplify
a)
b) 4 3
c) a
d) 4 3 6
a a a
x x
b a b
x y x y
Unit 14 CCM6+/7+ Page 9
Page 9
Let’s Try!
Simplify:
2 4
4 5
2 3
3 7 4
1)
2) 2 3
3) (6 )(2 )
4) (5 )(6 )
a a
x x
x y xy
x y x y
Find the area of each figure below. Write your answer is simplest
exponential form.
43x 39x
43x
26x
Unit 14 CCM6+/7+ Page 10
Page 10
Division Property of Exponents
Ex.
5
3
6 6 6 6 6 6 6
6 6 6 6 1
Ex.
4
2
x x x x xx
x x x
To divide numbers or variables with the same non-zero base, ____________ the
exponents. Or, look for where the base is “heavier” and leave the remainder.
Examples. Simplify each expression completely.
1. 7
3
10
10 2. 25
18
x
x
3. 24
27
5
5 4. 4
4
3
3
5. 512m
3m 6. 36b
18
7. 3
2
5
2
8. 5 6
8 3
x y
x y
9. 3
2
3
10. 2
4
5
Rule
Unit 14 CCM6+/7+ Page 11
Page 11
Exponents: Powers of a Power
You can use what you learned about multiplying numbers with powers to find a shortcut for
simplifying expressions with powers. Complete each statement by showing equivalent
expressions. Let your final answer be written as a base raised to a single power (exponential
form).
1.) (36)2 = 36 36 = _____ 2. (54)3 = 54 54 54 =
3.) (27)4 = ______ • ______ • ______ • ______ = 4. (45)5 = ______ • ______ • ______ • ______ • ______ =
5.) (14)6 = 6.) (62)4 =
Look at your answers.
What do you notice about the two exponents in
the original expression as compared to the value
of the exponent in the final expression?
What operation would allow you to go straight
from the original two exponents to the final one?
To simplify a power to a power, _________________________ the exponents.
Examples. Simplify each expression completely.
1. (22)3 2. (c5)4
3. (3●a)2 4. -52
5. (-5)2 6. (-4)2 ● -32
Rule
Unit 14 CCM6+/7+ Page 12
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Unit 14 CCM6+/7+ Page 13
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Unit 14 CCM6+/7+ Page 14
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Unit 14 CCM6+/7+ Page 15
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Unit 14 CCM6+/7+ Page 16
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Scientific Notation Notes (with powerpoint)
How wide is our universe?
210,000,000,000,000,000,000,000 miles
(_____ zeros) This number is written in _______________ ______________.
When numbers get this large, it is easier to write them in ____________ ___________.
A number is expressed in scientific notation when it is in the form
a x 10n
where ____ is between 1 and 10
and ___ is an integer
Write the width of the universe in scientific notation:
210,000,000,000,000,000,000,000 miles Where is the decimal point now?
Where would you put the decimal to make this number be between 1 and 10?
How many decimal places did you move the decimal?
When the original number is more than 1, the exponent is _________________.
The answer in scientific notation is:
Express 0.0000000902 in scientific notation.
Where would the decimal go to make the number be between 1 and 10?
The decimal was moved how many places?
When the original number is less than 1, the exponent is ____________________.
1) Write 28750.9 in scientific notation.
(choose one)
1. 2.87509 x 10-5
2. 2.87509 x 10-4
3. 2.87509 x 104
4. 2.87509 x 105
Unit 14 CCM6+/7+ Page 17
Page 17
2) Express 1.8 x 10-4 in standard notation.
3) Express 4.58 x 106 in standard notation.
Determine whether each of the following numbers is written in scientific notation? Explain.
Write each number in scientific notation.
4) 62,400
5) 0.00085
6) 1,602,000
Write each number in standard notation.
What does Scientific Notation look like on a calculator?
•Enter any 8-digit number into your calculator.
•Next, multiply by a 4-digit number.
•What do you see?
Unit 14 CCM6+/7+ Page 18
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Scientific Notation Homework
1. Is each number in scientific notation? If not, put the number in scientific notation.
1.6 x 10-6
950 x 105
0.84 x 10-5
8 x 103
2. Write 75,000,000,000 in scientific notation.
3. Write 0.0000429 in scientific notation.
4. Express 2.45 x 105 in standard form.
5. How much larger is 6 x 105 compared to 2 x 103
6. Which is the larger value: 2 x 106 or 9 x 105?
Unit 14 CCM6+/7+ Page 19
Page 19
7. A sample of bacteria triples every month. The expression 300 x 3m models a population of 300 bacteria
after m months of growth. Evaluate the expression for m = 0, 3, -2 and describe what each value of the
expression represents in the situation.
8. Recently, scientists have discovered 2 new moons. One moon’s distance from the sun is 234,000,000 miles,
while the other moon is 345,000,000 miles from the sun.
a. Write each number in scientific notation.
b. How many times closer to the sun is the first moon than the second moon? Write your answer in scientific
notation.
9. A person’s heart beats about 35 million beats in a year. If there are about 530 thousand minutes in a year,
what is the average heart rate in beats per minute?
10. The populations for four states are given below. List the states in order of their populations from least to
greatest.
Alaska: 6.19 x 105
Connecticut: 3.28 x 106
Hawaii: 1.18 x 106
North Carolina: 7.65 x 106
Unit 14 CCM6+/7+ Page 20
Page 20
Operations with Scientific Notation
Unit 14 CCM6+/7+ Page 21
Page 21
Multiplying with Scientific Notation
Example 1:
Example 2:
*The answer then must be changed to scientific
notation.
Example 3:
Example 4:
Dividing with Scientific Notation
Example 1:
*The answer then must be changed to scientific
notation.
Example 2:
Example 3:
Example 4:
How do the numbers compare to one another?
A. 4.5 106 B. 9 106 C. 4.5 107 How does B compare to A? How does C compare to A? How does A compare to C?
Unit 14 CCM6+/7+ Page 22
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Unit 14 CCM6+/7+ Page 23
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REAL WORLD APPLICATION
1) a. You are supposed to go to Idaho. It is 50 miles from here to Ogden. Then it is 90 miles to Pocatello
Idaho from Ogden. How far must you go?
b. You are supposed to go Venus. The earth is 9.3 x 107
miles from the sun. Venus is
8.5 x 1012 miles from the sun. How far is it to Venus?
2) a. You can travel 70 miles in one hour. How many hours will it take to get to Pocatello from Salt Lake
City?
b. You can travel 5.88 x 1012
miles in one light year. How many years will it take you to get to Venus?
3) a. The teeth of a comb are 3 millimeters wide. There are 45 teeth. How long is the comb?
b. A centipede’s leg is 7.23 x 10-2
cm. There are 50 legs on a side. How long is the centipede?
4) a. A bracelet weighs 8 oz. How many bracelets are in box which weighs a pound?
b. A grasshopper weighs 5.88 X 10-2
ounces. How many grasshoppers are in a pound? (a pound has 16
ounces)
5) Some stars in the Milky Way are 8 x 104 light years away.
Write this number in standard (expanded) form.
Why might scientists prefer to use this number in scientific notation?
6) A light year is 5.88 x 1012 miles.
Write this number in standard form.
Unit 14 CCM6+/7+ Page 24
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7) How many miles is it to the stars in the Milky Way: You’ll need the information in questions 1 and 2 to
answer this question. Show your work, including what you make the calculator do.
Write your answer in scientific notation.
8) If one eyelash measures 1.19 x 10-2 cm in diameter, and if your eyelashes lined up side by side in your eyelid
which measures 3 cm, how many eyelashes could fit on one eyelid?
Write your answer in standard form.
Write your answer in scientific notation.
If you lose 5 eyelashes per day, per eye, what percent of your total eyelashes are you losing per day?
9) A house spider weighs 4.22 x 10-3 ounces. How many house spiders are there in a pound? Note: there are
16 oz. in one pound. Show your work, including what you make the calculator do.
Unit 14 CCM6+/7+ Page 25
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Unit 13 Study Guide
EXPONENTS REVIEW
1. Any number to the power of zero always equals _________ because ____________________________
___________________________________________________________________________________.
2. If a number has a negative exponent, just __________________________________________________
___________________________________________________________________________________.
3. If two numbers with the same base are multiplying, just __________ the exponents.
4. If two numbers with the same base are dividing, just __________ the exponents.
5. If an exponent is beside a set of parentheses, just __________ it with the exponents inside the
parentheses.
6. If a negative sign is in front of parentheses that have an exponent outside, where does it fall in the
order of operations?
7. If a negative sign is inside parentheses that have an exponent outside, where does it fall in the order of
operations?
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 8.
a. –1 b. 0 c. –8.6 d. 1
____ 9.
a. b.
c.
d.
____ 10.
a.
b. 16 c.
d. –8
____ 11.
a.
b.
c.
d.
Unit 14 CCM6+/7+ Page 26
Page 26
____ 12.
a.
b.
c. d.
____ 13.
a. b. c. d.
____ 14.
a. b. c.
d.
____ 15.
a.
b. c.
d.
____ 16.
a. b. c. d.
____ 17.
a.
b.
c.
d.
SIMPLIFY. Pay attention to what you wrote above in the exponents review!
18. 72 75 19. a2b a3b4 20. nm
nm2
34
21. −(r5s4)0 22. 21
25
yx
yx
23. −2(2𝑥−3𝑦−1
4𝑥2𝑦−3)3
exponent
Unit 14 CCM6+/7+ Page 27
Page 27
SCIENTIFIC and STANDARD NOTATION—write the number in its equivalent other form.
24. 8,030,000,000 = ____________________ 25. 8.6 x 10-7 = ______________________
26. 8.72 x 105 = _____________________ 27. 0.0000073 = _____________________
Put in order from least to greatest.
28. 72 x 105, 6.9 x 106, 23 x 105 29. 19 x 10-3, 2.5 x 10-4, 1.89 x 10-4
Solve. Express your result in scientific notation.
30. 9.7821 x 10-17 + 3.14 x 10-18 31. 1.824 x 104 – 3.821 x 102
32. (1.5 x 105)(4 x 109) 32. (5.1 x 103)(1.63 x 10-5)
____ 33. Which number is written in scientific notation?
a. b. c. d.
____ 34. Which number is NOT written in scientific notation?
a. b. c. d.
____ 35. 0.0805
a. b. c. d.
Unit 14 CCM6+/7+ Page 28
Page 28
____ 36.
a. 9,000 b. c. 90,000 d. 360
____ 37. Order from least to greatest.
a. c. b. d.
____ 38. Which list shows the numbers in order from least to greatest?
a. c.
b. d.
____ 39.
a. b. c. d.
____ 40.
a. b. c. d.
____ 41. The diameter of Mercury is about miles. The diameter of Jupiter, the largest planet, is about
miles. What is the difference between the diameters of these planets expressed in scientific notation?
a. miles c. miles
b. miles d. miles
____ 42. The masses of four objects were measured during a physics experiment. The first and the last objects each
had a mass of 41.918 g. The second and the third objects each had a mass of 24.83 g. Find the total mass of the four
objects. Write your answer in scientific notation.
a. g c. g
b. g d. g
6.3 1064
6.3 1017
1.6 1064
1.6 1017