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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 
?? ????
 
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