Answer:
Yes, it is possible to have a relation on the set {a, b, c} that is both symmetric and transitive but not reflexive
Step-by-step explanation:
Let
Set A={a,b,c}
Now, define a relation R on set A is given by
R={(a,a),(a,b),(b,a),(b,b)}
For reflexive
A relation is called reflexive if (a,a)[tex]\in R[/tex] for every element a[tex]\in A[/tex]
[tex](c,c)\notin R[/tex]
Therefore, the relation R is not reflexive.
For symmetric
If [tex](a,b)\in R[/tex] then [tex](b,a)\in R[/tex]
We have
[tex](a,b)\in R[/tex] and [tex](b,a)\in R[/tex]
Hence, R is symmetric.
For transitive
If (a,b)[tex]\in R[/tex] and (b,c)[tex]\in R[/tex] then (a,c)[tex]\in R[/tex]
Here,
[tex](a,a)\in R[/tex] and [tex](a,b)\in R[/tex]
[tex]\implies (a,b)\in R[/tex]
[tex](a,b)\in R[/tex] and [tex](b,a)\in R[/tex]
[tex]\implies (a,a)\in R[/tex]
Therefore, R is transitive.
Yes, it is possible to have a relation on the set {a, b, c} that is both symmetric and transitive but not reflexive.