The product of a non-zero rational and an irrational number is
(A) always irrational
(B) always rational
(C) rational or irrational
(D) one

To do: 

We have to find the correct option.

Solution:

A rational number can be expressed in either terminating decimal or non-terminating recurring decimals and an irrational number is expressed in non-terminating non-recurring decimals.

$\sqrt{2}$ is an irrational number and $2$ is a rational number.

Therefore,

$2\times\sqrt{2}=2\sqrt{2}$which is an irrational number.

Hence, the product of a non-zero rational and an irrational number is always irrational.