If $R$ is an equivalence relation on a Set $A$, then $R^{-1}$ is not :-
Reflexive
Symmetric
Transitive
None of these
The minimum number of elements that must be added to the relation $R =\{( a , b ),( b , c )\}$ on the set $\{a, b, c\}$ so that it becomes symmetric and transitive is:
The relation "less than" in the set of natural numbers is
The relation "is subset of" on the power set $P(A)$ of a set $A$ is
$A$ relation $R$ is defined from $\{2, 3, 4, 5\}$ to $\{3, 6, 7, 10\}$ by $xRy \Leftrightarrow x$ is relatively prime to $y$. Then domain of $R$ is
Let $A=\{1,2,3\} .$ Then number of relations containing $(1,2)$ and $(1,3)$ which are reflexive and symmetric but not transitive is