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Copyright © Swun Math Grade 8 Unit 2 Lesson 7 P TE

7 P Zero and Negative Exponents 8.EE.1 1,

Procedural Lesson

Grade 8 · Unit 2 · Lesson 7
MC: 8.EE.1

Problem of the Day

Objective: I will evaluate expressions with zero and negative exponents.

Vocabulary Teacher Resources

Negative Exponent: indicates the number of

times to divide by the base

x−2

The negative sign says to do the inverse.

Dividing is the inverse of multiplying.

Reciprocal: what to multiply a value by to get 1;

multiplicative inverse

A negative exponent is equivalent to the inverse of

the positive of the same number.

x−3 is the reciprocal of x^3

4 −5 is the reciprocal of 45

Properties of Exponents

Zero Exponent a^0 = 1

Negative Exponent a−n=a^1 n

Considerations:

Show chart with pattern of exponents starting with

positive exponents and ending at zero exponent.

Show chart with pattern of exponents starting with

positive exponents and ending with a negative

exponent. Some students will recognize that the

power will “land” in the denominator if the larger

exponent is in the denominator. Example: x

4

x^6 =

1

x^2

Steps:

1. Write the expression in expanded form.


2. Simplify by canceling common factors.


3. Rewrite exponent as a positive exponent.
   OR


4. Subtract exponents of like bases.


5. Write answer using positive exponent.

Application of MPs:

MP1: How are negative exponents and reciprocals

related?

Negative exponents and reciprocals are

related because.

MP3: Why is the reciprocal of ퟓퟓ−ퟒퟒ, ퟏퟏퟓퟓퟒퟒ?

The reciprocal of 5 −4 is 514 because.

1 2 3 4 5 6 7 8

* * * * *

MPs

Applied MP

* Embedded MP

Student Journal Pages

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