Respuesta :

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.