Question:
If R is a relation from set A = (11, 12, 13) to set B = (8, 10, 12) defined by y = x − 3, then write R−1.
Solution:
Given:
A = (11, 12, 13) and B = (8, 10, 12)
R is defined by (y = x − 3) from A to B.
We know:
$8=11-3$
$10=13-3$
$\therefore R=\{(11,8),(13,10)\}$
Or,
$\mathrm{R}^{-1}=\{(8,11),(10,13)\}$