<< Chapter < Page Chapter >> Page >
This module is from Elementary Algebra by Denny Burzynski and Wade Ellis, Jr. This chapter contains many examples of arithmetic techniques that are used directly or indirectly in algebra. Since the chapter is intended as a review, the problem-solving techniques are presented without being developed. Therefore, no work space is provided, nor does the chapter contain all of the pedagogical features of the text. As a review, this chapter can be assigned at the discretion of the instructor and can also be a valuable reference tool for the student.

Overview

  • Factors
  • Exponential Notation

Factors

Let’s begin our review of arithmetic by recalling the meaning of multiplication for whole numbers (the counting numbers and zero).

Multiplication

Multiplication is a description of repeated addition.

In the addition

7 + 7 + 7 + 7

the number 7 is repeated as an addend* 4 times. Therefore, we say we have four times seven and describe it by writing

4 · 7

The raised dot between the numbers 4 and 7 indicates multiplication. The dot directs us to multiply the two numbers that it separates. In algebra, the dot is preferred over the symbol × to denote multiplication because the letter x is often used to represent a number. Thus,

4 · 7 = 7 + 7 + 7 + 7

Factors and products

In a multiplication, the numbers being multiplied are called factors. The result of a multiplication is called the product. For example, in the multiplication

4 · 7 = 28

the numbers 4 and 7 are factors, and the number 28 is the product. We say that 4 and 7 are factors of 28. (They are not the only factors of 28. Can you think of others?)

Now we know that

( factor ) · ( factor ) = product

This indicates that a first number is a factor of a second number if the first number divides into the second number with no remainder. For example, since

4 · 7 = 28

both 4 and 7 are factors of 28 since both 4 and 7 divide into 28 with no remainder.

Exponential notation

Quite often, a particular number will be repeated as a factor in a multiplication. For example, in the multiplication

7 · 7 · 7 · 7

the number 7 is repeated as a factor 4 times. We describe this by writing 7 4 . Thus,

7 · 7 · 7 · 7 = 7 4

The repeated factor is the lower number (the base), and the number recording how many times the factor is repeated is the higher number (the superscript). The superscript number is called an exponent.

Exponent

An exponent is a number that records how many times the number to which it is attached occurs as a factor in a multiplication.

Sample set a

For Examples 1, 2, and 3, express each product using exponents.

3 · 3 · 3 · 3 · 3 · 3.   Since 3 occurs as a factor 6 times,

3 · 3 · 3 · 3 · 3 · 3 = 3 6

Got questions? Get instant answers now!

8 · 8.   Since 8 occurs as a factor 2 times,

8 · 8 = 8 2

Got questions? Get instant answers now!

5 · 5 · 5 · 9 · 9.   Since 5 occurs as a factor 3 times, we have 5 3 . Since 9 occurs as a factor 2 times, we have 9 2 . We should see the following replacements.

5 · 5 · 5 5 3 · 9 · 9 9 2
Then we have

5 · 5 · 5 · 9 · 9 = 5 3 · 9 2

Got questions? Get instant answers now!

Expand 3 5 .   The base is 3 so it is the repeated factor. The exponent is 5 and it records the number of times the base 3 is repeated. Thus, 3 is to be repeated as a factor 5 times.

3 5 = 3 · 3 · 3 · 3 · 3

Got questions? Get instant answers now!

Expand 6 2 · 10 4 .   The notation 6 2 · 10 4 records the following two facts: 6 is to be repeated as a factor 2 times and 10 is to be repeated as a factor 4 times. Thus,

6 2 · 10 4 = 6 · 6 · 10 · 10 · 10 · 10

Got questions? Get instant answers now!

Exercises

For the following problems, express each product using exponents.

8 · 8 · 8

8 3

Got questions? Get instant answers now!

12 · 12 · 12 · 12 · 12

Got questions? Get instant answers now!

5 · 5 · 5 · 5 · 5 · 5 · 5

5 7

Got questions? Get instant answers now!

3 · 3 · 3 · 3 · 3 · 4 · 4

3 5 · 4 2

Got questions? Get instant answers now!

8 · 8 · 8 · 15 · 15 · 15 · 15

Got questions? Get instant answers now!

2 · 2 · 2 · 9 · 9 · 9 · 9 · 9 · 9 · 9 · 9

2 3 · 9 8

Got questions? Get instant answers now!

3 · 3 · 10 · 10 · 10

Got questions? Get instant answers now!

Suppose that the letters x and y are each used to represent numbers. Use exponents to express the following product.

x · x · x · y · y

x 3 · y 2

Got questions? Get instant answers now!

Suppose that the letters x and y are each used to represent numbers. Use exponents to express the following product.

x · x · x · x · x · y · y · y

Got questions? Get instant answers now!

For the following problems, expand each product (do not compute the actual value).

3 4

3 · 3 · 3 · 3

Got questions? Get instant answers now!

2 5

2 · 2 · 2 · 2 · 2

Got questions? Get instant answers now!

5 3 · 6 2

5 · 5 · 5 · 6 · 6

Got questions? Get instant answers now!

x 4 · y 4

x · x · x · x · y · y · y · y

Got questions? Get instant answers now!

For the following problems, specify all the whole number factors of each number. For example, the complete set of whole number factors of 6 is 1, 2, 3, 6.

20

1 , 2 , 4 , 5 , 10 , 20

Got questions? Get instant answers now!

12

1 , 2 , 3 , 4 , 6 , 12

Got questions? Get instant answers now!

21

1 , 3 , 7 , 21

Got questions? Get instant answers now!

Questions & Answers

how do you get the 2/50
Abba Reply
number of sport play by 50 student construct discrete data
Aminu Reply
width of the frangebany leaves on how to write a introduction
Theresa Reply
Solve the mean of variance
Veronica Reply
Step 1: Find the mean. To find the mean, add up all the scores, then divide them by the number of scores. ... Step 2: Find each score's deviation from the mean. ... Step 3: Square each deviation from the mean. ... Step 4: Find the sum of squares. ... Step 5: Divide the sum of squares by n – 1 or N.
kenneth
what is error
Yakuba Reply
Is mistake done to something
Vutshila
Hy
anas
hy
What is the life teble
anas
hy
Jibrin
statistics is the analyzing of data
Tajudeen Reply
what is statics?
Zelalem Reply
how do you calculate mean
Gloria Reply
diveving the sum if all values
Shaynaynay
let A1,A2 and A3 events be independent,show that (A1)^c, (A2)^c and (A3)^c are independent?
Fisaye Reply
what is statistics
Akhisani Reply
data collected all over the world
Shaynaynay
construct a less than and more than table
Imad Reply
The sample of 16 students is taken. The average age in the sample was 22 years with astandard deviation of 6 years. Construct a 95% confidence interval for the age of the population.
Aschalew Reply
Bhartdarshan' is an internet-based travel agency wherein customer can see videos of the cities they plant to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400 a. what is the probability of getting more than 12,000 hits? b. what is the probability of getting fewer than 9,000 hits?
Akshay Reply
Bhartdarshan'is an internet-based travel agency wherein customer can see videos of the cities they plan to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400. a. What is the probability of getting more than 12,000 hits
Akshay
1
Bright
Sorry i want to learn more about this question
Bright
Someone help
Bright
a= 0.20233 b=0.3384
Sufiyan
a
Shaynaynay
How do I interpret level of significance?
Mohd Reply
It depends on your business problem or in Machine Learning you could use ROC- AUC cruve to decide the threshold value
Shivam
how skewness and kurtosis are used in statistics
Owen Reply
yes what is it
Taneeya
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Elementary algebra. OpenStax CNX. May 08, 2009 Download for free at http://cnx.org/content/col10614/1.3
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Elementary algebra' conversation and receive update notifications?

Ask