Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
Let W denote the words in the English dictionary. Define the relation R by :
$R=\{(x, y) \in W \times W \mid$ the words $x$ and $y$ have at least one letter in common $\}$. Then $R$ is
MathematicsSets and RelationsJEE MainJEE Main 2006
Options:
  • A
    not reflexive, symmetric and transitive
  • B
    reflexive, symmetric and not transitive
  • C
    reflexive, symmetric and transitive
  • D
    reflexive, not symmetric and transitive
Solution:
1424 Upvotes Verified Answer
The correct answer is:
reflexive, symmetric and not transitive
Clearly $(\mathrm{x}, \mathrm{x}) \in \mathrm{R} \forall \mathrm{x} \in \mathrm{W}$. So, $\mathrm{R}$ is reflexive.
Let $(x, y) \in R$, then $(y, x) \in R$ as $x$ and $y$ have at least one letter in common. So, $R$ is symmetric.
But $R$ is not transitive for example
Let $x=$ DELHI, $y=$ DWARKA and $z=$ PARK
then $(x, y) \in R$ and $(y, z) \in R$ but $(x, z) \notin R$.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.