Determine whether each of the following relations are reflexive, symmetric and transitive:
Relation $\mathrm{R}$ in the set $\mathrm{A}=\{1,2,3,4,5,6\}$ as $\mathrm{R} =\{(\mathrm{x}, \mathrm{y}): \mathrm{y}$ is divisible by $\mathrm{x}\}$
$\mathrm{A}=\{1,2,3,4,5,6\}$
$\mathrm{R} =\{( \mathrm{x} , \mathrm{y} ): \mathrm{y} $ is divisible by $\mathrm{x} \}$
We know that any number $(\mathrm{x})$ is divisible by itself.
So, $(\mathrm{x}, \mathrm{x}) \in \mathrm{R}$
$\therefore \mathrm{R}$ is reflexive.
Now, $(2,4)\in \mathrm{R}$ $[$ as $4$ is divisible by $2]$
But, $(4,2) \notin \mathrm{R}$ . $[$ as $2$ is not divisible by $4]$
$\therefore \mathrm{R}$ is not symmetric.
Let $( \mathrm{x} , \mathrm{y} ),\,( \mathrm{y} , \mathrm{z} ) \in \mathrm{R} .$ Then, $\mathrm{y}$ is divisible by $\mathrm{x}$ and $\mathrm{z}$ is divisible by $\mathrm{y}$
$\therefore$ $ \mathrm{z}$ is divisible by $\mathrm{x}$ $\Rightarrow(\mathrm{x}, \mathrm{z}) \in \mathrm{R}$
$\therefore $ $\mathrm{R}$ is transitive.
Hence, $\mathrm{R}$ is reflexive and transitive but not symmetric.
Show that the relation $\mathrm{R}$ in the set $\mathrm{A}$ of points in a plane given by $\mathrm{R} =\{( \mathrm{P} ,\, \mathrm{Q} ):$ distance of the point $\mathrm{P}$ from the origin is same as the distance of the point $\mathrm{Q}$ from the origin $\}$, is an equivalence relation. Further, show that the set of all points related to a point $\mathrm{P} \neq(0,\,0)$ is the circle passing through $\mathrm{P}$ with origin as centre.
Show that the relation $R$ in the set $A=\{1,2,3,4,5\}$ given by $R =\{(a, b):|a-b|$ is even $\},$ is an equivalence relation. Show that all the elements of $\{1,3,5\}$ are related to each other and all the elements of $ \{2,4\}$ are
Let the relations $R_1$ and $R_2$ on the set $\mathrm{X}=\{1,2,3, \ldots, 20\}$ be given by $\mathrm{R}_1=\{(\mathrm{x}, \mathrm{y}): 2 \mathrm{x}-3 \mathrm{y}=2\}$ and $\mathrm{R}_2=\{(\mathrm{x}, \mathrm{y}):-5 \mathrm{x}+4 \mathrm{y}=0\}$. If $\mathrm{M}$ and $\mathrm{N}$ be the minimum number of elements required to be added in $R_1$ and $R_2$, respectively, in order to make the relations symmetric, then $\mathrm{M}+\mathrm{N}$ equals
Let $A=\{1,2,3, \ldots \ldots .100\}$. Let $R$ be a relation on A defined by $(x, y) \in R$ if and only if $2 x=3 y$. Let $R_1$ be a symmetric relation on $A$ such that $\mathrm{R} \subset \mathrm{R}_1$ and the number of elements in $\mathrm{R}_1$ is $\mathrm{n}$. Then, the minimum value of $n$ is..........................
Determine whether each of the following relations are reflexive, symmetric and transitive:
Relation $\mathrm{R}$ in the set $\mathrm{Z}$ of all integers defined as $\mathrm{R} =\{(\mathrm{x}, \mathrm{y}): \mathrm{x}-\mathrm{y}$ is an integer $\}$