Is this a transitive set of pairs?

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I want to determine wether the given relation is an equivalence relation on [$1$, $2$, $3$, $4$, $5$]. And If it is then list all the equivalence classes.

Relation: $\{(1, 1),(2, 2),(3, 3), (4, 4), (5, 5), (1, 5), (5, 1), (3, 5), (5, 3), (1, 3), (3, 1)\}$

My calculations:

It's reflexive since all numbers are related to themselves.

it's symetric.

I'm not sure if it's a transitive set. Since (4, 4), (2, 2) are alone and not connected to any others.

If it is transitive then how would you go about listing the equivalence classes?

Edit: I've gotten feedback now that says that it is transitive. So then I want to list the equivalence classes:

Some examples I have seen have definitions of the equivalence classes but this one doesn't so I assume all I gotta do is:

$[1] = \{ 1, 5, 3\}$

$[2] = \{ 2\}$

$[3] = \{ 3, 5, 1\}$

$[4] = \{ 4\}$

$[5] = \{ 5, 1, 3\}$

or something simillar?

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Yes the relation is transitive.

The only way that the relation would not be transitive, would be if there exists an $a,b,c$ such that $(a\sim b$ and $b\sim c),\,$ but $a \not \sim c$.

Equivalence Classes

Careful:

Each class must be pairwise disjoint. In your work, however, note that $[1] = [3]= [5] = \{1, 3, 5\}$

There should be only three equivalence classes: $[1] = \{1, 3, 5\}$, $\;[2] = \{2\},\;$ and $[4] = \{4\}$.

That's essentially what I think you are trying to say, But the relation defined in your question has only 3 unique (and disjoint) classes.