Evaluate:  (i) 3^-2   (ii) (-4)^-2   (iii) (1/2)^-5

Solution:

The exponent of a number shows how many times the number is multiplied by itself.

(i)  3^-2

According to the rules of exponents,

We know that a^-m = 1 / a^m for any non-zero integer

3^-2 = 1 / 3² = 1/9

(ii) (-4)^-2

We know that, a^-m = 1 / a^m for any non-zero integer

(-4)^-2 = 1 / (-4)^-2

= 1 / (-4 × -4)

= 1 / 16

(iii) (1/5)^-5

We know that, a^-m = 1 / a^m for any non-zero integer

(1/5)^-5 = 2⁵ = 2 × 2 × 2 × 2 × 2 = 32

☛ Check: NCERT Solutions for Class 8 Maths Chapter 12

Video Solution:

Evaluate (i) 3⁻² (ii) (4)⁻² (iii) (1/2)⁻⁵

Class 8 Maths NCERT Solutions Chapter 12 Exercise 12.1 Question 1

Summary:

The value of the following are (i) 3^-2 = 1/9, (ii) (-4)^-2 = 1 / 16 and (iii) (1/5)^-5 = 32

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