Name: ____________________________________ Date: __________________ Zero and Negative Exponents In our last lesson we learned how to simplify products and quotients of monomials using laws of exponents with positive integers. But, zero and negative exponents are also possible. Exercise #1: Recall that xa x a b . b x (a) Using this exponent law, simplify each of the following. x4 x4 x10 x10 y7 y7 (b) What must each of these quantities equal, assuming none of the variables equals zero? Exercise #2: Simplify each of the following: (a) 1250 (b) 2y 0 (c) 5x0 (d) 2x 0 3 We can investigate negative exponents in a very similar fashion to the zero exponent. The key is to define a negative exponent in such a way that our fundamental rules for exponents don’t need to change. x2 Exercise #3: Consider the quotient 5 . x (a) Write this quotient using the exponent law from Exercise #1. (b) Write this quotient in its simplest form without a negative exponent. Exercise #4: Rewrite each expression in simplest terms without the use of negative exponents. (a) 4 2 (b) x2 (c) 2 3 (d) y 10 Exercise #5: Rewrite each of the following monomials without the use of negative exponents. (a) 1 x 2 (b) 1 y 5 (c) 1 x 3 (d) y 5 x 7 NEGATIVE AND ZERO EXPONENTS If a is any integer and x 0 then (1) x a 1 xa (2) 1 xa a x (3) x0 1 x 2 y 5 Exercise #6: Which of the following is equivalent to 5 3 ? x y (1) x3 y8 (3) x3 y8 y8 (2) 3 x (4) 1 x y 3 8 Exercise #7: Rewrite the following expressions without negative or zero exponents. (a) 4 2 (b) 40 (c) 42 (g) 3x0 (h) 2x3 (i) 6 x 5 (d) 12 (e) 12 (j) 2x7 (k) a 3 d 2 (f) 1 0 (l) r 3t 2 s 4 Exercise #8: Evaluate each of the following expressions using the values a 1 , b 2 and c 3 . Use the STORE feature on your calculator to aid you. (a) ab 2 c 1 (b) abc 0 a 2 (c) 2 15 b c (d) abbcca Name: ____________________________________ Date: __________________ Zero and Negative Exponents Homework Skills For problems 1 through 36, rewrite without zero or negative exponents. 1. 4 3 17. 3 0 2 4. 10 1 20. 2 5. 4 6. 2 3 4 1 21. 2 1 22. 3 8. 1 40 24. 10. 3x 11. 5x 12. 27. x5 y 3 a 4 13. 3 b 0 2 14. 2x y 15. 2 3 38. y 3 for y 16. 16x 2 y 5 0 1 2 50 1 2 39. 2 x 4 y 1 for x 2, y 26. 2 1 0 4 37. y 3 for y 2 1 23. 16 25. 36. 2x 1 y 4 2 1 22 32 3x3 y 4 x0 y 3 35. z2 1 7. 9. 34. 33 2. 52 3. 5 x2 2 y 3 18. 8x 0 y 3 19. 0 33. 40. x 32 1 3 for x 4 2 1 2 41. x y for x 2, y 2 28. 2 29. 2 30. 2 x 3 y 2 4 x 4 y 1 2 1 31. a3b4 a 2 32. 4 b 42. x y 4 2 0 4 2 3 7 for x , y 2 4 5 3 43. x y x y for x , y Reasoning Fill in the missing each of the following. 44. 47. 55. Evaluate each of the following products: (a) 2 2 3 1 3 9 (c) 104 104 61. 37 34 27 62. a 63. 40 0 65. 1 (a) 2 x 51. 1 4 64 3 1 3 2x (b) 2x3 1 10, 000 1 3 81 1 a6 x 2 y 1 x 5 x 3 y 2 y 3 56. Which of the following is correct? 2 1 50. 2 3 64. 23 23 20 2 (d) xa xa 2 48. 62 49. 10 1 1 25 2 3 (b) 52 52 45. 42 46. for Find the value of x that makes each statement true. 66. 2 x 24 212 2 x3 Explain why the other choice is incorrect. 67. 52 5x 59 68. 4 x 2 410 True or False Write the answer to each of the following as a single number. 52. [1 5 2 ]3 1 57. 2 1 4 58. 3 1 0 2 1 1 53. 3 1 2 8 54. 31 3 3 59. 69. 3x2 27 2 2 2 4 3 70. 4 2 32 54 1 4 2 x 3 y 2 2 y 2 60. 3 5 a3 x 2 a x 71. 22 x 6 1 4 x 1