Q. The relation $R$ defined on the set of natural numbers as {($a,\ b$)$:a$ differs from $b$ by 3} is given by
A) {(1, 4), (2, 5), (3, 6), ...}
B) {(4, 1), (5, 2), (6, 3), ...}
C) {(1, 3), (2, 6), (3, 9), ...}
D) None of the above
Explanation
(b)
$R = \{(a,\ b):a,\ b \in N,\ a - b = 3\}$
$\ \ \ \ = \left\{ \left\lbrack (n + 3),\ n \right\rbrack:n \in N \right\}$
$\ \ \ \ = \{(4,\ 1),\ (5,\ 2),\ (6,\ 3),\ \ldots.\}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.