Which of the following is not correct for relation R

Question:

Which of the following is not correct for relation $R$ on the set of real numbers ?

  1. $(x, y) \in R \Leftrightarrow 0<|x|-|y| \leq 1$ is neither transitive nor symmetric.

  2. $(x, y) \in R \Leftrightarrow 0<|x-y| \leq 1$ is symmetric and transitive.

  3. $(x, y) \in R \Leftrightarrow|x|-|y| \leq 1$ is reflexive but not symmetric.

  4. $(x, y) \in R \Leftrightarrow|x-y| \leq 1$ is reflexive and symmetric.


Correct Option: , 2

Solution:

Note that $(1,2)$ and $(2,3)$ satisfy $0<|x-y| \leq 1$

but $(1,3)$ does not satisfy it so

$0 \leq|x-y| \leq 1$ is symmetric but not transitive

So, (2) is correct.

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