Exponents ICSE Class-8th Concise Selina Power Solutions

Exponents ICSE Class-8th Concise Selina Power Solutions Chapter-2. We provide step by step Solutions of Exercise / lesson-2 Exponents ICSE Class-8th Concise Selina Mathematics. Our Solutions contain all type Questions with Exe-2 A and Exe-2 B,  to develop skill and confidence. Visit official Website CISCE for detail information about ICSE Board Class-8.

Exponents ICSE Class-8th Concise Selina Power Solutions Chapter-2


–: Select Topics :–

Exe-2 A,

 Exe-2 B,


Laws of Exponents / Power

Law Example
x1 = x 61 = 6
x0 = 1 70 = 1
x-1 = 1/x 4-1 = 1/4
xmxn = xm+n x2x3 = x2+3 = x5
xm/xn = xm-n x6/x2 = x6-2 = x4
(xm)n = xmn (x2)3 = x2×3 = x6
(xy)n = xnyn (xy)3 = x3y3
(x/y)n = xn/yn (x/y)2 = x2 / y2
x-n = 1/xn x-3 = 1/x3
And the law about Fractional Exponents:
x^(m/n) = n-th root of (x^m) = (n-th root of x)^m x^(2/3) = 3rd root of (x^2) = (3rd root of x)^2

 Exercise – 2 A Exponents ICSE Class-8th Concise Selina Power Solutions

Question 1 :-

Evaluate:
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 1

Answer :-

Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 2
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 3
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 4
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 5
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 48

Question 2 :-

If 1125 = 3m x 5n; find m and n.

Answer 2:-

1125 = 32 x 53

The factor of 1125 are 3 x 3 x 5 x 5 x 5

3 1125
3 375
5 125
5 25
5 5
1

∴ 1125 = 3 x 3 x 5 x 5 x 5

Now comparing, 32 x 53 = 3m x 5n

∴ m = 2, n = 3

 

Question 3 :-

Find x, if 9 × 3x = (27)2x-3
Answer 3 :-

9 x 3x = (27) 2x-3

conise class 8 img 1

Since, bases are same, compare them,

x + 2 = 6x – 9

6x – x = 9 + 2

⇒ 5x = 11

⇒ x = 11/2

⇒ x = 215


 Exe -2 B  Exponents / Power ICSE Class-8th Concise selina 

Question 1 :-

Compute:
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 8
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 9

Answer 1 :-

Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 10
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 11
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 12
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 13
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 14
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 15
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 16
Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 17

Question 2 :-

Simplify:
(i) conise class 8 img 2
(ii) [(64)-2]-3 ÷ [{(-8)2}3]2
(iii) (2-3 – 2-4) (2-3 + 2-4)


Answer 2 :-

Selina Concise Mathematics Class 8 ICSE Solutions Chapter 2 Exponents (Powers) 18
(ii)

conise class 8 img 3 ans 2.2

(iii)

conise class 8 img 3 ans 2.3

Question 3 :-

Evaluate:
(i) (5)0
(ii) 80+40+20

(iii) (8+4+2)0

(iv) 4X0

(v) (4x)0

(vi) [(103)0)0]5

(vii) (7X0)2

(viii) 90+9-19-2+ 91/2 91/2

Answer 3:-

(i) (5)0

(5)0 =1

( a0 =1)

(ii) 

conise class 8 img 3 ans 3.2

(iii) 

conise class 8 img 3 ans 3.3

(iv) 

conise class 8 img 3 ans 3.4

(v) 

conise class 8 img 3 ans 3.5

(vi) 

conise class 8 img 3 ans 3.6

(vii) 

conise class 8 img 3 ans 3.7

(viii) 

90+9-19-291/2 − 91/2

conise class 8 img 3 ans 3.8

Question 4 :-

Simplify:

(i) conise class 8 img 3 ans 4.1

(ii) conise class 8 img 3 ans 4.2

(iii) conise class 8 img 3 ans 4.3

(iv) conise class 8 img 3 ans 4.4

(v) conise class 8 img 3 ans 4.5

(vi) conise class 8 img 3 ans 4.6

(vii)  conise class 8 img 3 ans 4.7

(viii)

Answer 4 :-

(i) conise class 8 img 3 ans 4.1 a

(ii) conise class 8 img 3 ans 4.2 a

(iii)  conise class 8 img 3 ans 4.3 a

(iv) conise class 8 img 3 ans 4.4 a

(v)conise class 8 img 3 ans 4.5 a

(vi) conise class 8 img 3 ans 4.6 a

(vii)  conise class 8 img 3 ans 4.7 a

(viii) conise class 8 img 3 ans 4.8 a

Question 5 :-

Simplify:
(xa+b)a-b.(xb+c)b-c.(xc+a)c-a

Answer 5 :-

(xa+b)a-b.(xb+c)b-c.(xc+a)c-a

(xa+b)(a-b).(xb+c)(b-c).(xc+a)(c-a)

=xa²-b². xb²-c².. xc²-a².

= x+b²- +

=x0

=1

Question 6 :-

Simplify:
(i) Exponents ICSE Class-8th Concise Selina Power Solutions ans 6
(ii) Exponents ICSE Class-8th Concise Selina Power Solutions ans 7

Answer 6 :-

(i) Exponents ICSE Class-8th Concise Selina Power Solutions ans 6 a

(ii)
Exponents ICSE Class-8th Concise Selina Power Solutions ans 7 a

Question 7 :-

(i) (a-2)-2. (ab)-3
(ii) (xny-m)× (x3y-2)-n
(iii) Exponents ICSE Class-8th Concise Selina Power Solutions ans 7.3
(iv)
(v) (a-2b)1/2 × (ab-3)1/3
(vi) (xy)m-n . (yz)n-1 . (zx)1-m


Answer 7 :-

(i) Exponents ICSE Class-8th Concise Selina Power Solutions ans 7

(ii) Exponents ICSE Class-8th Concise Selina Power Solutions ans 7.2

(iii) Exponents ICSE Class-8th Concise Selina Power Solutions ans 7.3 aExponents ICSE Class-8th Concise Selina Power Solutions ans 7.4

(iv) Exponents ICSE Class-8th Concise Selina Power Solutions ans 7.4 a

(v) Exponents ICSE Class-8th Concise Selina Power Solutions ans 7.5

(vi)  Exponents ICSE Class-8th Concise Selina Power Solutions ans 7.6

 

Question 8 :-

Show that:

Exponents ICSE Class-8th Concise Selina Power Solutions ans 8

Answer 8:-

Exponents ICSE Class-8th Concise Selina Power Solutions ans 8 a

 

Question 9 :-

Evaluate:

Exponents ICSE Class-8th Concise Selina Power Solutions ans 9

Answer 9 :-

Exponents ICSE Class-8th Concise Selina Power Solutions ans 9 a

 

Question 10 :-

Evaluate:

Exponents ICSE Class-8th Concise Selina Power Solutions ans 10

Answer 10 :-

Exponents ICSE Class-8th Concise Selina Power Solutions ans 10 a

 

Question 11 :-

(m + n)-1 (m-1 + n-1) = (mn)-1

Answer 11:-

Exponents ICSE Class-8th Concise Selina Power Solutions ans 11

Hence Proved.

 

Question 12 :-

Prove that:

(i) Exponents ICSE Class-8th Concise Selina Power Solutions ans 12.1

(ii)  Exponents ICSE Class-8th Concise Selina Power Solutions ans 12.2

Answer :-

(i)  Exponents ICSE Class-8th Concise Selina Power Solutions ans 12.1 a

(ii) Exponents ICSE Class-8th Concise Selina Power Solutions ans 12.2 a

Question 13 :-

Find the values of n, when:
(i) 12-5 × 122n+1 = 1213 ÷ 127
(ii)  Exponents ICSE Class-8th Concise Selina Power Solutions ans 13.2


Answer :-

(i)  Exponents ICSE Class-8th Concise Selina Power Solutions ans 13.1

(ii) Exponents ICSE Class-8th Concise Selina Power Solutions ans 13.2 a

Question 14 :-

Simplify:

(i) Exponents ICSE Class-8th Concise Selina Power Solutions ans 14.1

(ii)  Exponents ICSE Class-8th Concise Selina Power Solutions ans 14.2

Answer 14 :-

 

(i) Exponents ICSE Class-8th Concise Selina Power Solutions ans 14.1 a

(ii) Exponents ICSE Class-8th Concise Selina Power Solutions ans 14.2

— End of Exponents ICSE Class-8th Concise Solutions :–


Return to – Concise Selina Maths Solutions for ICSE Class -8


Thanks

 

Share with your friends

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.