If $R$ be a relation $<$ from $A = \{1,2, 3, 4\}$ to $B = \{1, 3, 5\}$ i.e., $(a,\,b) \in R \Leftrightarrow a < b,$ then $Ro{R^{ - 1}}$ is
$\{(1, 3), (1, 5), (2, 3), (2, 5), (3, 5), (4, 5)\}$
$\{(3, 1) (5, 1), (3, 2), (5, 2), (5, 3), (5, 4)\}$
$\{(3, 3), (3, 5), (5, 3), (5, 5)\}$
$\{(3, 3) (3, 4), (4, 5)\}$
Let $S$ be set of all real numbers ; then on set $S$ relation $R$ defined as $R = \{\ (a, b) : 1 + ab > 0\ \}$ is
The relation $R$ defined in $N$ as $aRb \Leftrightarrow b$ is divisible by $a$ is
Let $A=\{1,2,3\} .$ Then number of equivalence relations containing $(1,2)$ is
Let $X$ be a family of sets and $R$ be a relation on $X$ defined by $‘A$ is disjoint from $B’$. Then $R$ is
The relation $R$ defined on a set $A$ is antisymmetric if $(a,\,b) \in R \Rightarrow (b,\,a) \in R$ for