Question

$2\sqrt{2}-\sqrt{8}$ an rational or irrational number . If yes, justify your answer.

Answer 1

$2\sqrt{2}-\sqrt{8}=2\sqrt{2}-\sqrt{2\times 2\times 2}$

$=2\sqrt{2}-2\sqrt{2}=0$,

Hence, $0$ is a rational number.

So, $2\sqrt{2}-\sqrt{8}$ gives a rational number.