Let \[A=\{0,3,4,6,7,8,9,10\}\] and R be the relation defined on A such that \[R=\{(x, y) \in A \times A: x-y\] is odd positive integer or \[x-y=2\}\]. The minimum number of elements that must be added to the relation R, so that ...
Answer: 19
Solutions · 1
Official solution
We have, A=0,3,4,6,7,8,9,10
Case I : x−y is odd, if one is odd and one is even and x>y.
∴ Possibilites are {(3,0),(4,3),(6,3),(7,6),(7,4), (7,0),(8,7),(8,3),(9,8),(9,6),(9,4),(9,0),(10,9),(10, 7),(10,3)}
No. of cases =15
Case II : x−y=2∴ Possibilities are (6,4),(8,6),(9,7),(10,8)∴ No. of cases =4
So, minimum ordered pair to be added =15+4=19