Check sibling questions

Ex 1.3, 3 - Prove irrational :(i) 1/root(2) (ii) 7root(5) - Ex 1.3

Ex 1.3, 3 (i) - Chapter 1 Class 10 Real Numbers - Part 2

This video is only available for Teachoo black users


Introducing your new favourite teacher - Teachoo Black, at only β‚Ή83 per month


Ex 1.3 , 3 Prove that the following are irrationals : 1/√2 We have to prove 1/√2 is irrational Let us assume the opposite, i.e., 1/√2 is rational Hence, 1/√2 can be written in the form π‘Ž/𝑏 where a and b (bβ‰  0) are co-prime (no common factor other than 1) Hence, 1/√2 = π‘Ž/𝑏 (𝑏 )/π‘Ž= √2 " " Here, (𝑏 )/π‘Ž is a rational number But √2 is irrational Since, Rational β‰  Irrational This is a contradiction ∴ Our assumption is incorrect Hence 1/√2 is irrational Hence proved

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.