SELINA Solutions for Class 9 Maths Chapter 7 - Indices (Exponents)

Page / Exercise

Chapter 7 - Indices (Exponents) Exercise Ex. 7(A)

Question 1

Evaluate:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(iii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(iv) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(v) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 1

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

 

(iii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

 

(iv)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

(v)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 2

Simplify:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(iii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(iv) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

Solution 2

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

(iii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

(iv)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

 

Question 3

Evaluate:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

Solution 3

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

Question 4

Simplify each of the following and express with positive index:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(iii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(iv) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 4

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(iii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(iv)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 5

If 2160 = 2a. 3b. 5c, find a, b and c. Hence calculate the value of 3a Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents2-b Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents5-c.

Solution 5

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 6

If 1960 = 2a. 5b. 7c, calculate the value of 2-a. 7b. 5-c.

Solution 6

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

 

Question 7

Simplify:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents


(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 7

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 8

Show that:

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 8

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 9

If a = xm + n. yl; b = xn + l. . ym and c = xl + m. yn,

Prove that: am - n. bnl. cl - m = 1

Solution 9

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 10

Simplify:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 10

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Chapter 7 - Indices (Exponents) Exercise Ex. 7(B)

Question 1

Solve for x:

(i) 22x+1 = 8

(ii) 25x-1 = 4 Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents23x + 1

(iii) 34x + 1 = (27)x + 1

(iv) (49)x + 4 = 72Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents (343)x + 1

Solution 1

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(iii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(iv)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 2

Find x, if:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(iii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(iv) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 2

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(iii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents


(iv)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 3

Solve:

(i) 4x - 2 - 2x + 1 = 0

(ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 3

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 4

Solve :

(i) 8 Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents22x + 4Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 2x+1 = 1 + 2x

(ii)22x + 2x+2 - 4 Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents23 = 0

(iii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 4

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

(iii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 5

Find the values of m and n if:

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 5

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 6

 

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 6

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Question 7

Prove that:

(i) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents=1

 

 (ii) Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 7

(i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

(ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 8

If ax = b, by = c and cz = a, prove that: xyz = 1.

Solution 8

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 9

If ax = by = cz and b2 = ac, prove that : Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 9

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 10

If 5-P = 4-q = 20r, show that:

 

 

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Solution 10

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Question 11

If m ≠ n and (m + n)-1 (m-1 + n-1) = mxny, show that:

 

 

x + y + 2 = 0

 

Solution 11

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Question 12

If 5x + 1 = 25x - 2, find the value of

 

 

3x - 3 × 23 - x

 

Solution 12

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Question 13

If 4x + 3 = 112 + 8 × 4x, find the value of (18x)3x.

 

 

 

 

Solution 13

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Question 14 (i)

Solve for x:

 4x-1 × (0.5)3 - 2x = Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

Solution 14 (i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

  

 

 

 

 

Question 14 (ii)

Solve for x:


(a3x + 5)2. (ax)4 = a8x + 12

 

Solution 14 (ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Question 14 (iii)

Solve for x:

 Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Solution 14 (iii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

 

Question 14 (iv)

Solve for x:

23x + 3 = 23x + 1 + 48

 

Solution 14 (iv)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

 

 

 

Question 14 (v)

Solve for x:


3(2x + 1) - 2x + 2 + 5 = 0

 

Solution 14 (v)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

 

Question 14 (vi)

9x+2 = 720 + 9x

Solution 14 (vi)

9x+2 = 720 + 9x

9x+2 - 9x = 720

9x (92 - 1) = 720

9x (81 - 1) = 720

9x (80) = 720

9x = 9

9x = 91

x = 1

Chapter 7 - Indices (Exponents) Exercise Ex. 7(C)

Question 1

Selina Solutions Icse Class 9 Mathematics Chapter - Indices ExponentsSelina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 1

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 2

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 2

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 3

Solve: 3x-1× 52y-3 = 225.

Solution 3

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 4

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 4

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 5

If 3x+1 = 9x-3, find the value of 21+x.

Solution 5

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 6

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 6

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 7

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 7

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 8

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 8

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 9

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 9

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 10

Solve: 3(2x + 1) - 2x+2 + 5 = 0.

Solution 10

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 11

If (am)n = am .an, find the value of:

m(n - 1) - (n - 1)

Solution 11

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 12

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 12

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents 

Question 13

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 13

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 14

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 14

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 15 (i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 15 (i)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 15 (ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 15 (ii)

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Question 16

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents

Solution 16

Selina Solutions Icse Class 9 Mathematics Chapter - Indices Exponents