<< Chapter < Page Chapter >> Page >

x 5 x 2 = x x x x x x x = ( x x ) x x x ( x x ) = x x x = x 3 . Notice that 5 2 = 3 .

Got questions? Get instant answers now!

a 8 a 3 = a a a a a a a a a a a = ( a a a ) a a a a a ( a a a ) = a a a a a = a 5 . Notice that 8 3 = 5 .

Got questions? Get instant answers now!

Quotient rule for exponents

If x is a real number and n and m are natural numbers,

x n x m = x n m , x 0 .

To divide two exponential quantities having the same nonzero base, subtract the exponent of the denominator from the exponent of the numerator. Keep in mind that the exponential quantities being divided must have the same base for this rule to apply.

Sample set c

Find the following quotients. All exponents are natural numbers.

x 5 x 2 = x 5-2 = x 3 The part in the box is usally done mentally .

Got questions? Get instant answers now!

27 a 3 b 6 c 2 3 a 2 b c = 9 a 3 2 b 6 1 c 2 1 = 9 a b 5 c

Got questions? Get instant answers now!

15 x 3 x = 5 x

The bases are the same, so we subtract the exponents. Although we don’t know exactly what is, the notation indicates the subtraction.

Got questions? Get instant answers now!

Practice set c

Find each quotient

( x + 6 ) 5 ( x + 6 ) 3

( x + 6 ) 2

Got questions? Get instant answers now!

26 x 4 y 6 z 2 13 x 2 y 2 z

2 x 2 y 4 z

Got questions? Get instant answers now!

When we make the subtraction, n m , in the division x n x m , there are three possibilities for the values of the exponents:

  1. The exponent of the numerator is greater than the exponent of the denominator, that is, n > m . Thus, the exponent, n m , is a natural number.
  2. The exponents are the same, that is, n = m . Thus, the exponent, n m , is zero, a whole number.
  3. The exponent of the denominator is greater than the exponent of the numerator, that is, n < m . Thus, the exponent, n m , is an integer.

Zero as an exponent

In Sample Set C, the exponents of the numerators were greater than the exponents of the denominators. Let’s study the case when the exponents are the same.

When the exponents are the same, say n , the subtraction n n produces 0.

Thus, by the second rule of exponents, x n x n = x n n = x 0 .

But what real number, if any, does x 0 represent? Let’s think for a moment about our experience with division in arithmetic. We know that any nonzero number divided by itself is one.

8 8 = 1 , 43 43 = 1 , 258 258 = 1

Since the letter x represents some nonzero real number, so does x n . Thus, x n x n

represents some nonzero real number divided by itself. Then x n x n = 1 .

But we have also established that if x 0 , x n x n = x 0 . We now have that x n x n = x 0

and x n x n = 1 . This implies that x 0 = 1 , x 0 .

Exponents can now be natural numbers and zero. We have enlarged our collection of numbers that can be used as exponents from the collection of natural numbers to the collection of whole numbers.

Zero as an exponent

If x 0 , x 0 = 1

Any number, other than 0, raised to the power of 0, is 1. 0 0 has no meaning (it does not represent a number).

Sample set d

Find each value. Assume the base is not zero.

2 x 2 x 2 = 2 x 0 = 2 1 = 2

Got questions? Get instant answers now!

5 ( x + 4 ) 8 ( x 1 ) 5 5 ( x + 4 ) 3 ( x 1 ) 5 = ( x + 4 ) 8 3 ( x 1 ) 5 5 = ( x + 4 ) 5 ( x 1 ) 0 = ( x + 4 ) 5

Got questions? Get instant answers now!

Practice set d

Find each value. Assume the base is not zero.

6 x 4 2 x 3

3 x 4 3 = 3 x

Got questions? Get instant answers now!

14 a 7 7 a 2

2 a 7 2 = 2 a 5

Got questions? Get instant answers now!

26 x 2 y 5 4 x y 2

13 2 x y 3

Got questions? Get instant answers now!

36 a 4 b 3 c 8 8 a b 3 c 6

9 2 a 3 c 2

Got questions? Get instant answers now!

51 ( a 4 ) 3 17 ( a 4 )

3 ( a 4 ) 2

Got questions? Get instant answers now!

52 a 7 b 3 ( a + b ) 8 26 a 2 b ( a + b ) 8

2 a 5 b 2

Got questions? Get instant answers now!

14 x r y p z q 2 x r y h z 5

7 y p h z q 5

Got questions? Get instant answers now!

We will study the case where the exponent of the denominator is greater than the exponent of the numerator in Section [link] .

Exercises

Use the product rule and quotient rule of exponents to simplify the following problems. Assume that all bases are nonzero and that all exponents are whole numbers.

12 x y 3 z 2 4 x 2 y 2 z 3 x

144 x 4 y 5 z 3

Got questions? Get instant answers now!

( 4 x 2 ) ( 8 x y 3 )

32 x 3 y 3

Got questions? Get instant answers now!

( 2 x y ) ( 3 y ) ( 4 x 2 y 5 )

Got questions? Get instant answers now!

( 1 4 a 2 b 4 ) ( 1 2 b 4 )

1 8 a 2 b 8

Got questions? Get instant answers now!

( 3 8 ) ( 16 21 x 2 y 3 ) ( x 3 y 2 )

Got questions? Get instant answers now!

15 x 20 y 24 z 4 5 x 19 y z

Got questions? Get instant answers now!

24 x 4 y 4 z 0 w 8 9 x y w 7

Got questions? Get instant answers now!

a 4 b 6 ( a 10 b 16 a 5 b 7 )

a 9 b 15

Got questions? Get instant answers now!

3 a 2 b 3 ( 14 a 2 b 5 2 b )

Got questions? Get instant answers now!

( x + 3 y ) 11 ( 2 x 1 ) 4 ( x + 3 y ) 3 ( 2 x 1 )

( x + 3 y ) 8 ( 2 x 1 ) 3

Got questions? Get instant answers now!

40 x 5 z 10 ( z x 4 ) 12 ( x + z ) 2 10 z 7 ( z x 4 ) 5

Got questions? Get instant answers now!

x n x n + 3

x 2 n + 3

Got questions? Get instant answers now!

a Δ a b b

a Δ + b +

Got questions? Get instant answers now!

Exercises for review

( [link] ) What natural numbers can replace x so that the statement 5 < x 3 is true?

Got questions? Get instant answers now!

( [link] ) Use the distributive property to expand 4 x ( 2 a + 3 b ) .

8 a x + 12 b x

Got questions? Get instant answers now!

( [link] ) Express x x x y y y y ( a + b ) ( a + b ) using exponents.

Got questions? Get instant answers now!

( [link] ) Find the value of 4 2 + 3 2 2 3 10 8 .

8

Got questions? Get instant answers now!

( [link] ) Find the value of 4 2 + ( 3 + 2 ) 2 1 2 3 5 + 2 4 ( 3 2 2 3 ) 4 2 .

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