Help understanding anti- symmetric and irreflexive property

68 Views Asked by At

Hi i have been working on a question is R anti-symmetric, irreflexive? A ={1,2,3,4} R= {(1,3),(1,2),(3,2),(4,4)}

I worked out R is not anti- symmetric and is not irreflexive since (4,4) is related. The answer states i am wrong, can someone please help me understand this as other definitions have not help. Thank you in advance

1

There are 1 best solutions below

4
On BEST ANSWER

A relation $R$ is anti symmetric iff $$ (aRb \text { & } bRa) \implies a=b$$

This is what we have with our $R$.

The only case of $$ (aRb \text { & } bRa)$$ is $4R4$ and we have $4=4$ which makes our relation anti-symmetric.