Chapter 2 Number System Ex 2.2

RBSE Solutions for Class 9 Maths Chapter 2 Number System Ex 2.2

Question 1.
Classify the following numbers as rational or irrational.

Solution:
(i) 2 – √5 is an irrational number.
(ii) (3 + √23) – √23 = 3 + √23 – √23 = 3
Hence, it is a rational number.

Hence, it a rational number.
(iv)  is an irrational number.
(v) 2π is an irrational number.

Question 2.
Rationalist the denominator of the following:

Solution:

Question 3.
, where a and b are rational, then find the values of a and b.
Solution:

Rationalizing the denominator of L.H.S. by multiplying and dividing by 3 + √2