1 Lessons # 8.3-8.4: Zero and Negative Exponents; Scientific Notation Objectives: Use zero and negative exponents. Read and write numbers in scientific notation. Homework Assignment: Study # 8.3-8.4; Review notes/examples; Handouts for # 8.3-8.4 8.3 Define and Use Zero and Negative Exponents DEFINITION OF ZERO AND NEGATIVE EXPONENTS Words a to the zero power a0 is 1. a–n is the reciprocal of an. an is the reciprocal of a–n. Algebra a0 = ____, a ≠ 0 Example 50 = ____ a–n = ____ ,a ≠ 0 2–1 = ____ an = ____ ,a ≠ 0 2 = ____ Example 1 a. 2–3 = 1 3 4 c. = b. (-10)° = d. 0–7 = 2 PROPERTIES OF EXPONENTS Let a and b be real numbers, and let m and n be integers. am. an = a ______ ____________________ property (am)n = a ____ ____________________ property (ab)m = _______ ____________________ property am = a _____ , a ≠ 0 an m a = ____ b ≠ 0 b ____________________ property ____________________ property b Example 2 a. (-5)4 • (-5)– 4 = b. (5-2)–2 = c. 1 = 42 2 d. 3 = 31 Checkpoint. 1. 1 1 8 b 6 1 3. 6 1 2. 32 4. (5–1)2 3 Example 3 Simplify the expression. Write your answer using only positive exponents. a) Checkpoint. 4 5. 6 fg 2f2g 6. (3yz2)–2 8.5. SCIENTIFIC NOTATION A number is written in scientific notation when it is of the form___________ where 1 ≤ c < 10 and n is an integer. Number Standard form Scientific notation Sixteen million ____________ _______________ Two ____________ _______________ hundredths Example 4 Write numbers in scientific notation a. 7,820,000 = b. 0.00401 = Example 5 Write numbers in standard form a. 3.89 × 109 = b. 9.097 × 10–5 = 4 Checkpoint. 7. a) Write the number 0.0899 in scientific notation: b) Write the number 6.0001 x 107 in standard form: Example 6 Order 3.2 × 10–4, 0.0004, and 2.8 x 10–5 from least to greatest: Example 7 Evaluate the expression. Write your answer in scientific notation. a. (5.6 x 10–4)(1.4 x 10–5) = b. (3.2 x 102)3 = c. 3.5 × 10 –3 1.75 × 10 –5 Checkpoint. Simplify the expression. 8. (2.01×10–7)2 = 9. 4.8 × 10–4 6 × 10–4