Give an example of a set A with equivalence relations R and S for which S∘R ≠ R∘S

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I have to give an mere example where SR is not equal to RS.

I have tried a couple of numerical examples but am not able to figure any out.

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Somehow I've never come across relation composition before!

Anyway, this should work. Let $A = \{a, b, c\}$. Let $R$ equate $a, b$ and leave $c$ alone. Let $S$ equate $b, c$ and leave $a$ alone.

Then $aRSc$ but we don't have $aSRc$.

Let me know if I misunderstood the definition and I'll edit or delete my post.