6-1

1. 6-1 Integer Exponents Warm Up Lesson Presentation Lesson Quiz Holt McDougal Algebra 1 Holt Algebra 1

2.  5  5  5  5 You have seen positive exponents. Recall that to simplify 32, use 3 as a factor 2 times: 32 = 3  3 = 9. But what does it mean for an exponent to be negative or 0? You can use a table and look for a pattern to figure it out. 55 54 53 52 51 50 5–1 5–2 625 3125 125 25 5

3. When the exponent decreases by one, the value of the power is divided by 5. Continue the pattern of dividing by 5.

5. Example 2: Zero and Negative Exponents Simplify. A. 4–3 B. 70 Any nonzero number raised to the zero power is 1. 7º = 1 C. (–5)–4 D. –5–4

6. Use the definition Example 3A: Evaluating Expressions with Zero and Negative Exponents Evaluate the expression for the given value of the variables. x–2 for x = 4 Substitute 4 for x.

7. Example 3B: Evaluating Expressions with Zero and Negative Exponents Simplify the expression for the given values of the variables. –2a0b-4 for a = 5 and b = –3 Substitute 5 for a and –3 for b. Evaluate expressions with exponents. Write the power in the denominator as a product. Simplify the denominator. Simplify.

8. for a = –2 and b = 6 Check It Out! Example 3b Evaluate the expression for the given values of the variables. Substitute –2 for a and 6 for b. Simplify expressions with exponents. Write the power in the denominator as a product. Simplify the denominator. 2 Simplify.

9. B. Example 4: Simplifying Expressions with Zero and Negative Numbers Simplify. A. 7w–4

10. and Example 4: Simplifying Expressions with Zero and Negative Numbers Simplify. C.

11. rº = 1 and . Check It Out! Example 4 Simplify. a. 2r0m–3 b. c.