No products in the cart.

Show that root 2 is an …

CBSE, JEE, NEET, CUET

CBSE, JEE, NEET, CUET

Question Bank, Mock Tests, Exam Papers

NCERT Solutions, Sample Papers, Notes, Videos

Show that root 2 is an irrational number.
  • 2 answers

Sia ? 4 years, 7 months ago

Let us assume that {tex}\sqrt2{/tex} is a rational number.
So it can be expressed in the form p/q where p, q are co-prime integers and q {tex}\ne{/tex} 0
{tex}\sqrt2{/tex} = p/q
Here p and q are coprime numbers and q {tex}\ne{/tex} 0
Solving
{tex}\sqrt2{/tex} = p/q
On squaring both the side we get,
{tex}\Rightarrow{/tex} 2 = (p/q)2
{tex}\Rightarrow{/tex} 2q2 = p2 .. (1)
p2/2 = q2
So 2 divides p and p is a multiple of 2.
{tex}\Rightarrow{/tex} p = 2m
{tex}\Rightarrow{/tex} p2 = 4m2 ..(2)
From equations (1) and (2), we get,
2q2 = 4m2
{tex}\Rightarrow{/tex} q2 = 2m2
{tex}\Rightarrow{/tex} q2 is a multiple of 2
{tex}\Rightarrow{/tex} q is a multiple of 2
Hence, p, q have a common factor 2. This contradicts our assumption that they are co-primes. Therefore, p/q is not a rational number
{tex}\sqrt2{/tex} is an irrational number.

Mayank Choudhary 4 years, 7 months ago

Let us assume that ✓2 is a rational number. So it can be expressed in the form p/q where p, q are co-prime integers and q 0 = p/q Here p and q are coprime numbers and q 0 Solving = p/q On squaring both the side we get, 2 = (p/q)2 2q2 = p2 .. (1) p2/2 = q2 So 2 divides p and p is a multiple of 2. p = 2m p2 = 4m2 ..(2) From equations (1) and (2), we get, 2q2 = 4m2 q2 = 2m2 q2 is a multiple of 2 q is a multiple of 2 Hence, p, q have a common factor 2. This contradicts our assumption that they are co-primes. Therefore, p/q is not a rational number Hence it is proved that ✓2 is irrational number
https://examin8.com Test

Related Questions

X-y=5
  • 1 answers
Venu Gopal has twice
  • 0 answers
(A + B )²
  • 1 answers
Find the nature of quadratic equation x^2 +x -5 =0
  • 0 answers
Prove that root 8 is an irration number
  • 2 answers
sin60° cos 30°+ cos60° sin 30°
  • 2 answers

myCBSEguide App

myCBSEguide

Trusted by 1 Crore+ Students

Test Generator

Test Generator

Create papers online. It's FREE.

CUET Mock Tests

CUET Mock Tests

75,000+ questions to practice only on myCBSEguide app

Download myCBSEguide App