Question

number of set values of (p,q), which satisfy relation p^2 = 2q^2 ( where p and q are natural numbers )

options:
(A) 1
(B) 0
(C) 2
(D) 3

Answer 1

(B) 0

We have

$p^2 = 2q^2 \implies \dfrac{p^2}{q^2} = \left(\dfrac pq\right)^2 = 2$

but 2 is not a square number.