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Page 1 EXPONENTS AND POWERS Points to Remember Recall that we may write 3×3×3×3 as 3 4 and read it as three raise to the power four. In 3 4 , we call 3 as base and 4 as exponent. Similarly, when an integer ‘a’ is multiplied ‘n’ times the result is expressed as a n . Here ‘a’ is called the base and ‘n’ is called as exponent. ? LAWS OF EXPONENTS: (i). a m × a n = a m + n (ii). ?? ?? ?? ?? = a m - n (iii). ( a m ) n = a m x n (iv). a m × b m = (ab) m (v). a m ÷ b m = ( ?? ?? ) m (vi). a - m = ?? ?? ?? ? Further we recall that (i). a 0 = 1 (ii). (- 1) even number = 1 (iii). (- 1) odd number = - 1 ? STANDARD FORM: When a number is expressed as a decimal between 1.0 and 10.0 multiplied by a power of 10 is called its standard form. Thus A × 10 n is the standard form where 1 = A< 10, n is an integer. For example, a number 2806196 can be expressed in standard form as 2.806196 × 10 6 Questions: 1. What is the base and exponent of 10 – 3 ? 2. Write in exponential form: (-2) × (-2) × (-2) × (-2) × (-2) × (-2). Page 2 EXPONENTS AND POWERS Points to Remember Recall that we may write 3×3×3×3 as 3 4 and read it as three raise to the power four. In 3 4 , we call 3 as base and 4 as exponent. Similarly, when an integer ‘a’ is multiplied ‘n’ times the result is expressed as a n . Here ‘a’ is called the base and ‘n’ is called as exponent. ? LAWS OF EXPONENTS: (i). a m × a n = a m + n (ii). ?? ?? ?? ?? = a m - n (iii). ( a m ) n = a m x n (iv). a m × b m = (ab) m (v). a m ÷ b m = ( ?? ?? ) m (vi). a - m = ?? ?? ?? ? Further we recall that (i). a 0 = 1 (ii). (- 1) even number = 1 (iii). (- 1) odd number = - 1 ? STANDARD FORM: When a number is expressed as a decimal between 1.0 and 10.0 multiplied by a power of 10 is called its standard form. Thus A × 10 n is the standard form where 1 = A< 10, n is an integer. For example, a number 2806196 can be expressed in standard form as 2.806196 × 10 6 Questions: 1. What is the base and exponent of 10 – 3 ? 2. Write in exponential form: (-2) × (-2) × (-2) × (-2) × (-2) × (-2). 3. Write in exponential form a × b ×a × b × b. 4. Find the value of (-2) 2 × (-2) 3 5. If 4 3 = 4 x , then find x. 6. Express 64 x 27 in exponential form. 7. Express 2000000 in standard form. 8. What is usual form of 3.469 × 10 6 ? 9. Simplify: (2 -1 × 3 - 1 × 4 -1 ) 2 . 10. Change into negative exponent ( ?? ?? ) ?? . 11. Simplify: (1234) 0 × 2 3 × x 2 × y. 12. Find the value of 9 0 × 99 0 × 125 0 × 256 0 . 13. Find the value of (a 0 + b 0 ) × (a 0 - b 0 ). 14. Find the reciprocal of ?? ???? . 15. Simplify: 2 3 × 2 5 × 2 7 . 16. Simplify: ( ?? ???? ) 2 × (- 6) 3 17. Express ?????? ?????? in exponential form. 18. If a 2 b 3 = a 2x b y . Find x and y. 19. Simplify: (2p 3 ) 3 ÷ 3 (p 2 ) 3 20. Find value of (???? ) - ?? ?? × (???? ) ?? ?? 21. Simplify: ?? ?? ?? ?? ?? ???? ?? ?? ?? ?? 22. Find the value of ((???? ) ?? ?? + (???? ) ?? ?? ) . 23. Find the value of (- ?? ???? ) ?? ?? 24. Find the reciprocal of ( - ?? ?? ) 2 Page 3 EXPONENTS AND POWERS Points to Remember Recall that we may write 3×3×3×3 as 3 4 and read it as three raise to the power four. In 3 4 , we call 3 as base and 4 as exponent. Similarly, when an integer ‘a’ is multiplied ‘n’ times the result is expressed as a n . Here ‘a’ is called the base and ‘n’ is called as exponent. ? LAWS OF EXPONENTS: (i). a m × a n = a m + n (ii). ?? ?? ?? ?? = a m - n (iii). ( a m ) n = a m x n (iv). a m × b m = (ab) m (v). a m ÷ b m = ( ?? ?? ) m (vi). a - m = ?? ?? ?? ? Further we recall that (i). a 0 = 1 (ii). (- 1) even number = 1 (iii). (- 1) odd number = - 1 ? STANDARD FORM: When a number is expressed as a decimal between 1.0 and 10.0 multiplied by a power of 10 is called its standard form. Thus A × 10 n is the standard form where 1 = A< 10, n is an integer. For example, a number 2806196 can be expressed in standard form as 2.806196 × 10 6 Questions: 1. What is the base and exponent of 10 – 3 ? 2. Write in exponential form: (-2) × (-2) × (-2) × (-2) × (-2) × (-2). 3. Write in exponential form a × b ×a × b × b. 4. Find the value of (-2) 2 × (-2) 3 5. If 4 3 = 4 x , then find x. 6. Express 64 x 27 in exponential form. 7. Express 2000000 in standard form. 8. What is usual form of 3.469 × 10 6 ? 9. Simplify: (2 -1 × 3 - 1 × 4 -1 ) 2 . 10. Change into negative exponent ( ?? ?? ) ?? . 11. Simplify: (1234) 0 × 2 3 × x 2 × y. 12. Find the value of 9 0 × 99 0 × 125 0 × 256 0 . 13. Find the value of (a 0 + b 0 ) × (a 0 - b 0 ). 14. Find the reciprocal of ?? ???? . 15. Simplify: 2 3 × 2 5 × 2 7 . 16. Simplify: ( ?? ???? ) 2 × (- 6) 3 17. Express ?????? ?????? in exponential form. 18. If a 2 b 3 = a 2x b y . Find x and y. 19. Simplify: (2p 3 ) 3 ÷ 3 (p 2 ) 3 20. Find value of (???? ) - ?? ?? × (???? ) ?? ?? 21. Simplify: ?? ?? ?? ?? ?? ???? ?? ?? ?? ?? 22. Find the value of ((???? ) ?? ?? + (???? ) ?? ?? ) . 23. Find the value of (- ?? ???? ) ?? ?? 24. Find the reciprocal of ( - ?? ?? ) 2 25. Express ?????? ???? in exponential form. 26. Express ?????? ?????? in exponential form. 27. Simplify: [(?? ?? ?? ) 3/8 ] 2 28. Simplify: ( ?? ?? ) -?? × ( ?? ?? ) ?? × a 3 × b 3 29. What is usual form of 2.29 × 10 4 . 30. If ( ?? ?? ) 2 × ( ?? ?? ) t = 1, then find the value of t. 31. The speed of light is 300000000 m/s. Express it in standard form. 32. Change in to positive exponent ( ?? ?? ) - ?? . 33. Change in to negative exponent ( ?? ?? ) ?? . 34. If ?? ???? = 64, then find the value of x. 35. Find the value of x if ?? ???? × ?? ?? = ?? ?? . 36. What number is obtained from expanded form 5 × ???? ?? + 2 × ???? ?? + 5× ???? ?? + 2 × ???? ?? + ???? ?? 37. The distance of moon from earth is 384000 km, express it in standard form. 38. If ?? ?? = ( ?? ?? ) ?? -( ?? ?? ) ?? , then find the value of ?? ?? . 39. Find the value of ( ?? -?? - ?? -?? ) × ???? ?? . 40. If ?? ?? × ?? ?? = 64 ×81, then find the value of x + y. 41. What is the standard form of the number 2467895? 42. Find the value of x: ( - ?? ?? ) ???? ÷ (- ?? ?? ) ?? = (- ?? ?? ) ???? + ?? 43. Simplify and express in exponential form: { ( ?? ?? ) ?? × ?? ?? } ÷{?? ?? × ?? ?? } Page 4 EXPONENTS AND POWERS Points to Remember Recall that we may write 3×3×3×3 as 3 4 and read it as three raise to the power four. In 3 4 , we call 3 as base and 4 as exponent. Similarly, when an integer ‘a’ is multiplied ‘n’ times the result is expressed as a n . Here ‘a’ is called the base and ‘n’ is called as exponent. ? LAWS OF EXPONENTS: (i). a m × a n = a m + n (ii). ?? ?? ?? ?? = a m - n (iii). ( a m ) n = a m x n (iv). a m × b m = (ab) m (v). a m ÷ b m = ( ?? ?? ) m (vi). a - m = ?? ?? ?? ? Further we recall that (i). a 0 = 1 (ii). (- 1) even number = 1 (iii). (- 1) odd number = - 1 ? STANDARD FORM: When a number is expressed as a decimal between 1.0 and 10.0 multiplied by a power of 10 is called its standard form. Thus A × 10 n is the standard form where 1 = A< 10, n is an integer. For example, a number 2806196 can be expressed in standard form as 2.806196 × 10 6 Questions: 1. What is the base and exponent of 10 – 3 ? 2. Write in exponential form: (-2) × (-2) × (-2) × (-2) × (-2) × (-2). 3. Write in exponential form a × b ×a × b × b. 4. Find the value of (-2) 2 × (-2) 3 5. If 4 3 = 4 x , then find x. 6. Express 64 x 27 in exponential form. 7. Express 2000000 in standard form. 8. What is usual form of 3.469 × 10 6 ? 9. Simplify: (2 -1 × 3 - 1 × 4 -1 ) 2 . 10. Change into negative exponent ( ?? ?? ) ?? . 11. Simplify: (1234) 0 × 2 3 × x 2 × y. 12. Find the value of 9 0 × 99 0 × 125 0 × 256 0 . 13. Find the value of (a 0 + b 0 ) × (a 0 - b 0 ). 14. Find the reciprocal of ?? ???? . 15. Simplify: 2 3 × 2 5 × 2 7 . 16. Simplify: ( ?? ???? ) 2 × (- 6) 3 17. Express ?????? ?????? in exponential form. 18. If a 2 b 3 = a 2x b y . Find x and y. 19. Simplify: (2p 3 ) 3 ÷ 3 (p 2 ) 3 20. Find value of (???? ) - ?? ?? × (???? ) ?? ?? 21. Simplify: ?? ?? ?? ?? ?? ???? ?? ?? ?? ?? 22. Find the value of ((???? ) ?? ?? + (???? ) ?? ?? ) . 23. Find the value of (- ?? ???? ) ?? ?? 24. Find the reciprocal of ( - ?? ?? ) 2 25. Express ?????? ???? in exponential form. 26. Express ?????? ?????? in exponential form. 27. Simplify: [(?? ?? ?? ) 3/8 ] 2 28. Simplify: ( ?? ?? ) -?? × ( ?? ?? ) ?? × a 3 × b 3 29. What is usual form of 2.29 × 10 4 . 30. If ( ?? ?? ) 2 × ( ?? ?? ) t = 1, then find the value of t. 31. The speed of light is 300000000 m/s. Express it in standard form. 32. Change in to positive exponent ( ?? ?? ) - ?? . 33. Change in to negative exponent ( ?? ?? ) ?? . 34. If ?? ???? = 64, then find the value of x. 35. Find the value of x if ?? ???? × ?? ?? = ?? ?? . 36. What number is obtained from expanded form 5 × ???? ?? + 2 × ???? ?? + 5× ???? ?? + 2 × ???? ?? + ???? ?? 37. The distance of moon from earth is 384000 km, express it in standard form. 38. If ?? ?? = ( ?? ?? ) ?? -( ?? ?? ) ?? , then find the value of ?? ?? . 39. Find the value of ( ?? -?? - ?? -?? ) × ???? ?? . 40. If ?? ?? × ?? ?? = 64 ×81, then find the value of x + y. 41. What is the standard form of the number 2467895? 42. Find the value of x: ( - ?? ?? ) ???? ÷ (- ?? ?? ) ?? = (- ?? ?? ) ???? + ?? 43. Simplify and express in exponential form: { ( ?? ?? ) ?? × ?? ?? } ÷{?? ?? × ?? ?? } 44. What is the standard form of the number 0.0032456? 45. Simplify: ( ?? - ?? × ?? - ?? × ?? ) ?? . 46. If ?? ???? = ?????? ?? , find the value of x. 47. Find the value of x if, ( ?? ?? ÷ ?? - ?? )× ?? ???? = ?? ?? 48. Simplify: ( ?? ?? ) - ?? + ( ?? ?? ) - ?? + ( ?? ?? ) - ?? 49. Find the reciprocal of ( ?? ?? ) - ?? ÷ ( ?? ?? ) - ?? . 50. Simplify: ( ?? ?? ) ?? × ( ?? ?? ) ?? ?? ?? ×( ?? ?? ) ?? Page 5 EXPONENTS AND POWERS Points to Remember Recall that we may write 3×3×3×3 as 3 4 and read it as three raise to the power four. In 3 4 , we call 3 as base and 4 as exponent. Similarly, when an integer ‘a’ is multiplied ‘n’ times the result is expressed as a n . Here ‘a’ is called the base and ‘n’ is called as exponent. ? LAWS OF EXPONENTS: (i). a m × a n = a m + n (ii). ?? ?? ?? ?? = a m - n (iii). ( a m ) n = a m x n (iv). a m × b m = (ab) m (v). a m ÷ b m = ( ?? ?? ) m (vi). a - m = ?? ?? ?? ? Further we recall that (i). a 0 = 1 (ii). (- 1) even number = 1 (iii). (- 1) odd number = - 1 ? STANDARD FORM: When a number is expressed as a decimal between 1.0 and 10.0 multiplied by a power of 10 is called its standard form. Thus A × 10 n is the standard form where 1 = A< 10, n is an integer. For example, a number 2806196 can be expressed in standard form as 2.806196 × 10 6 Questions: 1. What is the base and exponent of 10 – 3 ? 2. Write in exponential form: (-2) × (-2) × (-2) × (-2) × (-2) × (-2). 3. Write in exponential form a × b ×a × b × b. 4. Find the value of (-2) 2 × (-2) 3 5. If 4 3 = 4 x , then find x. 6. Express 64 x 27 in exponential form. 7. Express 2000000 in standard form. 8. What is usual form of 3.469 × 10 6 ? 9. Simplify: (2 -1 × 3 - 1 × 4 -1 ) 2 . 10. Change into negative exponent ( ?? ?? ) ?? . 11. Simplify: (1234) 0 × 2 3 × x 2 × y. 12. Find the value of 9 0 × 99 0 × 125 0 × 256 0 . 13. Find the value of (a 0 + b 0 ) × (a 0 - b 0 ). 14. Find the reciprocal of ?? ???? . 15. Simplify: 2 3 × 2 5 × 2 7 . 16. Simplify: ( ?? ???? ) 2 × (- 6) 3 17. Express ?????? ?????? in exponential form. 18. If a 2 b 3 = a 2x b y . Find x and y. 19. Simplify: (2p 3 ) 3 ÷ 3 (p 2 ) 3 20. Find value of (???? ) - ?? ?? × (???? ) ?? ?? 21. Simplify: ?? ?? ?? ?? ?? ???? ?? ?? ?? ?? 22. Find the value of ((???? ) ?? ?? + (???? ) ?? ?? ) . 23. Find the value of (- ?? ???? ) ?? ?? 24. Find the reciprocal of ( - ?? ?? ) 2 25. Express ?????? ???? in exponential form. 26. Express ?????? ?????? in exponential form. 27. Simplify: [(?? ?? ?? ) 3/8 ] 2 28. Simplify: ( ?? ?? ) -?? × ( ?? ?? ) ?? × a 3 × b 3 29. What is usual form of 2.29 × 10 4 . 30. If ( ?? ?? ) 2 × ( ?? ?? ) t = 1, then find the value of t. 31. The speed of light is 300000000 m/s. Express it in standard form. 32. Change in to positive exponent ( ?? ?? ) - ?? . 33. Change in to negative exponent ( ?? ?? ) ?? . 34. If ?? ???? = 64, then find the value of x. 35. Find the value of x if ?? ???? × ?? ?? = ?? ?? . 36. What number is obtained from expanded form 5 × ???? ?? + 2 × ???? ?? + 5× ???? ?? + 2 × ???? ?? + ???? ?? 37. The distance of moon from earth is 384000 km, express it in standard form. 38. If ?? ?? = ( ?? ?? ) ?? -( ?? ?? ) ?? , then find the value of ?? ?? . 39. Find the value of ( ?? -?? - ?? -?? ) × ???? ?? . 40. If ?? ?? × ?? ?? = 64 ×81, then find the value of x + y. 41. What is the standard form of the number 2467895? 42. Find the value of x: ( - ?? ?? ) ???? ÷ (- ?? ?? ) ?? = (- ?? ?? ) ???? + ?? 43. Simplify and express in exponential form: { ( ?? ?? ) ?? × ?? ?? } ÷{?? ?? × ?? ?? } 44. What is the standard form of the number 0.0032456? 45. Simplify: ( ?? - ?? × ?? - ?? × ?? ) ?? . 46. If ?? ???? = ?????? ?? , find the value of x. 47. Find the value of x if, ( ?? ?? ÷ ?? - ?? )× ?? ???? = ?? ?? 48. Simplify: ( ?? ?? ) - ?? + ( ?? ?? ) - ?? + ( ?? ?? ) - ?? 49. Find the reciprocal of ( ?? ?? ) - ?? ÷ ( ?? ?? ) - ?? . 50. Simplify: ( ?? ?? ) ?? × ( ?? ?? ) ?? ?? ?? ×( ?? ?? ) ?? ANSWERS 1 Base= 10, Exponent = - 3 26 ( ?? ?? ) ?? or ?? ?? ?? ?? 2 (-?? ) ?? 27 ?? ?? /?? 3 ?? ?? ?? ?? 28 ?? ?? 4 -???? 29 22900 5 x = 3 30 ?? = -?? 6 ?? ?? ?? ?? 31 ?? . ?? × ???? ?? m/s 7 ?? × ???? ?? 32 ( ?? ?? ) ?? 8 3469000 33 ( ?? ?? ) -???? 9 ?? ?????? 34 ?? = ?? ?? 10 ( ?? ?? ) -?? 35 ?? = ?? 11 ?? ?? ?? ?? 36 52521 12 1 37 ?? . ???? × ???? ?? km 13 0 38 - ???? ???? 14 ???? ?? 39 - ?? ???? 15 ?? ???? 40 ?? + ?? = 10 16 - ?? ?? 41 ?? . ???????????? × ???? ?? 17 ?? ?? ?? ?? 42 ?? = ?? 18 ?? = ?? , ?? = ?? 43 ?? ?? 19 ?? ?? ?? ?? 44 ?? . ???????? × ???? -?? 20 ?? ?? 45 ?? ?? 21 ?? ?? ?? ?? 46 ?? = ?? 22 100 47 ?? = ???? 23 ?? ???? 48 29 24 9 49 ???? ?? 25 ?? ?? ?? ?? 50 ?? ????Read More
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