# Polynomials

## Integer Exponents and Scientific Notation


### Use the Definition of a Negative Exponent

We saw that the Quotient Property for Exponents introduced earlier in this chapter, has two forms depending on whether the exponent is larger in the numerator or the denominator.
What if we just subtract exponents regardless of which is larger?
Let’s consider .
We subtract the exponent in the denominator from the exponent in the numerator.
We can also simplify  by dividing out common factors:
This implies that  and it leads us to the definition of a negative exponent.
The negative exponent tells us we can re-write the expression by taking the reciprocal of the base and then changing the sign of the exponent.
Any expression that has negative exponents is not considered to be in simplest form. We will use the definition of a negative exponent and other properties of exponents to write the expression with only positive exponents.
For example, if after simplifying an expression we end up with the expression , we will take one more step and write . The answer is considered to be in simplest form when it has only positive exponents.
In  we raised an integer to a negative exponent. What happens when we raise a fraction to a negative exponent? We’ll start by looking at what happens to a fraction whose numerator is one and whose denominator is an integer raised to a negative exponent.
This leads to the Property of Negative Exponents.
Suppose now we have a fraction raised to a negative exponent. Let’s use our definition of negative exponents to lead us to a new property.
To get from the original fraction raised to a negative exponent to the final result, we took the reciprocal of the base—the fraction—and changed the sign of the exponent.
This leads us to the Quotient to a Negative Power Property.
When simplifying an expression with exponents, we must be careful to correctly identify the base.
We must be careful to follow the Order of Operations. In the next example, parts (a) and (b) look similar, but the results are different.
When a variable is raised to a negative exponent, we apply the definition the same way we did with numbers. We will assume all variables are non-zero.
When there is a product and an exponent we have to be careful to apply the exponent to the correct quantity. According to the Order of Operations, we simplify expressions in parentheses before applying exponents. We’ll see how this works in the next example.
With negative exponents, the Quotient Rule needs only one form , for . When the exponent in the denominator is larger than the exponent in the numerator, the exponent of the quotient will be negative.


### Simplify Expressions with Integer Exponents

All of the exponent properties we developed earlier in the chapter with whole number exponents apply to integer exponents, too. We restate them here for reference.
In the next two examples, we’ll start by using the Commutative Property to group the same variables together. This makes it easier to identify the like bases before using the Product Property.
In the next two examples, we’ll use the Power Property and the Product to a Power Property.
To simplify a fraction, we use the Quotient Property and subtract the exponents.

### Convert from Decimal Notation to Scientific Notation

Remember working with place value for whole numbers and decimals? Our number system is based on powers of 10. We use tens, hundreds, thousands, and so on. Our decimal numbers are also based on powers of tens—tenths, hundredths, thousandths, and so on. Consider the numbers 4,000 and . We know that 4,000 means  and 0.004 means .
If we write the 1000 as a power of ten in exponential form, we can rewrite these numbers in this way:
When a number is written as a product of two numbers, where the first factor is a number greater than or equal to one but less than 10, and the second factor is a power of 10 written in exponential form, it is said to be in scientific notation.
It is customary in scientific notation to use as the  multiplication sign, even though we avoid using this sign elsewhere in algebra.
If we look at what happened to the decimal point, we can see a method to easily convert from decimal notation to scientific notation.
In both cases, the decimal was moved 3 places to get the first factor between 1 and 10.


### Convert Scientific Notation to Decimal Form

How can we convert from scientific notation to decimal form? Let’s look at two numbers written in scientific notation and see.
If we look at the location of the decimal point, we can see an easy method to convert a number from scientific notation to decimal form.
In both cases the decimal point moved 4 places. When the exponent was positive, the decimal moved to the right. When the exponent was negative, the decimal point moved to the left.
The steps are summarized below.

### Multiply and Divide Using Scientific Notation

Astronomers use very large numbers to describe distances in the universe and ages of stars and planets. Chemists use very small numbers to describe the size of an atom or the charge on an electron. When scientists perform calculations with very large or very small numbers, they use scientific notation. Scientific notation provides a way for the calculations to be done without writing a lot of zeros. We will see how the Properties of Exponents are used to multiply and divide numbers in scientific notation.

### Key Concepts

1. Property of Negative Exponents


2. Quotient to a Negative Exponent


3. To convert a decimal to scientific notation:


4. To convert scientific notation to decimal form:



### Section Exercises


### Practice Makes Perfect

Use the Definition of a Negative Exponent
In the following exercises, simplify.
Simplify Expressions with Integer Exponents
In the following exercises, simplify.
Convert from Decimal Notation to Scientific Notation
In the following exercises, write each number in scientific notation.
Convert Scientific Notation to Decimal Form
In the following exercises, convert each number to decimal form.
Multiply and Divide Using Scientific Notation
In the following exercises, multiply. Write your answer in decimal form.
In the following exercises, divide. Write your answer in decimal form.

### Everyday Math


### Writing Exercises


### Self Check

ⓐ After completing the exercises, use this checklist to evaluate your mastery of the objectives of this section.
ⓑ Overall, after looking at the checklist, do you think you are well-prepared for the next section? Why or why not?

### Chapter 6 Review Exercises


### Add and Subtract Polynomials

Identify Polynomials, Monomials, Binomials and Trinomials
In the following exercises, determine if each of the following polynomials is a monomial, binomial, trinomial, or other polynomial.
Determine the Degree of Polynomials
In the following exercises, determine the degree of each polynomial.
Add and Subtract Monomials
In the following exercises, add or subtract the monomials.
Add and Subtract Polynomials
In the following exercises, add or subtract the polynomials.
Evaluate a Polynomial for a Given Value of the Variable
In the following exercises, evaluate each polynomial for the given value.

### Use Multiplication Properties of Exponents

Simplify Expressions with Exponents
In the following exercises, simplify.
Simplify Expressions Using the Product Property for Exponents
In the following exercises, simplify each expression.
Simplify Expressions Using the Power Property for Exponents
In the following exercises, simplify each expression.
Simplify Expressions Using the Product to a Power Property
In the following exercises, simplify each expression.
Simplify Expressions by Applying Several Properties
In the following exercises, simplify each expression.
Multiply Monomials
In the following exercises 8, multiply the monomials.

### Multiply Polynomials

Multiply a Polynomial by a Monomial
In the following exercises, multiply.
Multiply a Binomial by a Binomial
In the following exercises, multiply the binomials using: ⓐ the Distributive Property, ⓑ the FOIL method, ⓒ the Vertical Method.
In the following exercises, multiply the binomials. Use any method.
Multiply a Trinomial by a Binomial
In the following exercises, multiply using ⓐ the Distributive Property, ⓑ the Vertical Method.
In the following exercises, multiply. Use either method.

### Special Products

Square a Binomial Using the Binomial Squares Pattern
In the following exercises, square each binomial using the Binomial Squares Pattern.
Multiply Conjugates Using the Product of Conjugates Pattern
In the following exercises, multiply each pair of conjugates using the Product of Conjugates Pattern.
Recognize and Use the Appropriate Special Product Pattern
In the following exercises, find each product.

### Divide Monomials

Simplify Expressions Using the Quotient Property for Exponents
In the following exercises, simplify.
Simplify Expressions with Zero Exponents
In the following exercises, simplify.
Simplify Expressions Using the Quotient to a Power Property
In the following exercises, simplify.
Simplify Expressions by Applying Several Properties
In the following exercises, simplify.
Divide Monomials
In the following exercises, divide the monomials.

### Divide Polynomials

Divide a Polynomial by a Monomial
In the following exercises, divide each polynomial by the monomial.
Divide a Polynomial by a Binomial
In the following exercises, divide each polynomial by the binomial.

### Integer Exponents and Scientific Notation

Use the Definition of a Negative Exponent
In the following exercises, simplify.
Simplify Expressions with Integer Exponents
In the following exercises, simplify.
Convert from Decimal Notation to Scientific Notation
In the following exercises, write each number in scientific notation.
Convert Scientific Notation to Decimal Form
In the following exercises, convert each number to decimal form.
Multiply and Divide Using Scientific Notation
In the following exercises, multiply and write your answer in decimal form.
In the following exercises, divide and write your answer in decimal form.

### Chapter Practice Test

In the following exercises, simplify each expression.
In the following exercises, simplify, and write your answer in decimal form.