Question

Prove that 5 root 7is a irrational number

Answer 1

Answer:

Prove that 5√7 is irrational.

We know that the product of two rational numbers is rational. ∴ 5√7×15 is rational. ⇒ √7 is rational. But square root of prime number is always an irrational numb

Answer 2

Let A= 5root7
Then A/5 = root 7
As root 7 is irrational
So A/5 is irrational
Ie A is irrational
Hence 5root7 is irrational