1. Class 9
2. Important Questions for Exam - Class 9

Transcript

Ex1.5, 1 Classify the following numbers as rational or irrational: (i) 2 - √5 2 is rational √5 = 2.236…. which is non- terminating non-repeating is an irrational number We know that Rational – Irrational = Irrational 2 - √5 is an irrational number Ex1.5, 1 Classify the following numbers as rational or irrational: (ii) (3 + √23) – √23 (3 + √23) – √23 = 3 + √23 – √23 = 3 = 3/1 Since it is of the form 𝑝/𝑞 So, it is a rational number. Ex1.5, 1 Classify the following numbers as rational or irrational: (iii)  (2√7)/(7√7) (2√7)/(7√7) = 2/7, Since it is of the form 𝑝/𝑞 So, it is a rational number. Ex1.5, 1 Classify the following numbers as rational or irrational: (iv)  1/√2 1 is rational √2 " = 1.4142…" which is non- terminating non-repeating is an irrational number We know that 𝑅𝑎𝑡𝑖𝑜𝑛𝑎𝑙/𝐼𝑟𝑟𝑎𝑡𝑖𝑜𝑛𝑎𝑙 = Irrational So, 1/√2 is irrational number Ex1.5, 1 Classify the following numbers as rational or irrational: (v)  2𝜋 2 is rational 𝜋 = 3.1415…. which is non- terminating non-repeating is an irrational number We know that Rational × Irrational = Irrational Thus, 2𝜋 is an irrational number

Class 9
Important Questions for Exam - Class 9