Question:
The product of a non-zero rational and an irrational number is
(a) always irrational
(b) always rational
(c) rational or irrational
(d) one
Solution:
(a) Product of a non-zero rational and an irrational number is always irrational i.e.,
$\frac{3}{4} \times \sqrt{2}=\frac{3 \sqrt{2}}{4}$ (irrational).