Give an example of a relation which is reflexive and transitive but not symmetric.

Explanation

Define a relation `R` in `\mathbf{R}` as:
$$ \left.R=\{a, b): a^{3} \geq b^{3}\right\} $$
Clearly `(a, a) \in R` as `a^{3}=a^{3}`.


`\therefore R` is reflexive.


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