Math 2 Lesson 1-4 Zero and Negative Exponents Name ___________________________ Date _______________ I can solve problems using properties of exponents learned in previous courses, extending the properties from integer bases to variable bases. The pond at North Chagrin Reservation fills up with lily pads every year. Lily pads reproduce rapidly, doubling in population every day! You go the pond today (day zero) and count 32 lily pads. A week later, you return to find 4096 lily pads! 1. Fill in the following table. Day Number of Lily Pads Value written as a power of 2. -4 four days ago -3 -2 -1 0 today 1 tomorrow 2 32 64 32 21 32 2 2 3 4 5 6 7 one week from today 4096 32 2 7 2. What happened to the lily pad population as time moved forward? 3. What happened to the lily pad population as time moved backward? 4. What happened when your exponent was 0? 5. What happened when your exponent was negative? 6. NOTES: In what two ways can we simplify the following expression? w8 w8 Explain what this fact means about the two different expressions? 7. Use what you discovered in problem (6) to evaluate the following: 50 _____ 61160 _____ x 0 _____ 2 0 _____ 89 8. ZERO POWER PROPERTY: When b is any base and b 0 , b0 _____ 9. NOTES: In what two ways can we simplify the following expression? 0 w5 w8 Explain what this fact means about the two different expressions? _____ 0 _____ 9. Evaluate the following. 21 _____ 10. 11. 32 22 _____ 32 23 _____ 32 24 _____ 1 32 _____ 2 1 32 _____ 4 1 32 _____ 8 1 32 _____ 16 So what can we conclude from the above results? Answer the following using fractions only! 22 _____ 23 _____ 24 _____ Let’s see what happens when we raise other numbers (bases) to negative exponents. Write your answers as simplified fractions. 43 _____ 82 _____ 53 _____ Let’s convert our answers from above to fractions with positive exponents. Fill in the blanks. 31 1 3 14. 24 _____ 32 21 _____ 31 _____ 13. 23 _____ Now let’s explore what happens when we have a negative exponent. 21 _____ 12. 22 _____ 82 1 43 8 1 4 One conclusion we can draw about negative exponents is… NEGATIVE EXPONENTS PROPERTY: When b is any base and b 0 , b x 1 b 5 3 1 5 15. Simplify the following. Write your answers as simplified fractions. 1 4 5 16. ______________ 3 4 4 5 ______________ ______________ 4 5 ______________ Let’s convert our answers from above to fractions with positive exponents. Fill in the blanks. 1 2 5 4 5 4 17. 2 4 5 3 5 4 5 4 4 5 4 5 4 5 4 5 4 The other conclusion we can draw about negative exponents is… NEGATIVE EXPONENTS PROPERTY: When a and b are not equal to zero, 18. a b x b a Simplify the following. Use only positive exponents in your answers. 1 x y 2 2 ______________ a b ______________ 5x 7y 3 ______________ 2h j ______________ Math 2 Name ___________________________ Lesson 1-4 Zero and Negative Exponents Homework I can solve problems using properties of exponents learned in previous courses, extending the properties from integer bases to variable bases. Simplify completely. Leave your answers as fractions. No negative exponents! 1.) 5 3 2.) 7 2 3.) 6 1 4.) b 7 5.) 2 5 6.) 3 2 7.) a b 8.) x 2y 9.) 19 0 10.) 7 11.) y0 12.) abcdefg 4 1 3 8 0 0 What if a negative exponent appears in the bottom of a fraction? 1 1 23 1 23 213 1 1 x5 x 5 1 4 b 4 c 4 b c 4 b4 c Simply put, if you get a base with a negative exponent in the denominator, move it to the numerator with a positive exponent. Simplify completely. Leave your answers as fractions. No negative exponents! 13.) 1 y 6 14.) 1 8 3 15.) x 7 y 5 16.) 23 w6 x 4 y 5 z 2