Proof that $ 1_A cup s cdot s cdot s $ is equivalence relation












1












$begingroup$


I have problem with this task:

Proof that $$ 1_A cup s cdot s cdot s $$ is equivalence relation

where $r subset A times A$ and $r$ is a relation such that
$$ forall_{x,y,z} r(x,y) wedge r(x,z) rightarrow r(y,z) $$ and
$$ s = r cup r^{-1} $$



Reflexivity results directly from the definition and symmetry results from the symmetry of the relationship $s$. This part was not difficult for me, but I am trying to show that this relation is transitive and I have no idea how to show that...










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  • $begingroup$
    What is maneuverability?
    $endgroup$
    – William Elliot
    Jan 20 at 0:10










  • $begingroup$
    reflexivity @WilliamElliot
    $endgroup$
    – VirtualUser
    Jan 20 at 0:38
















1












$begingroup$


I have problem with this task:

Proof that $$ 1_A cup s cdot s cdot s $$ is equivalence relation

where $r subset A times A$ and $r$ is a relation such that
$$ forall_{x,y,z} r(x,y) wedge r(x,z) rightarrow r(y,z) $$ and
$$ s = r cup r^{-1} $$



Reflexivity results directly from the definition and symmetry results from the symmetry of the relationship $s$. This part was not difficult for me, but I am trying to show that this relation is transitive and I have no idea how to show that...










share|cite|improve this question











$endgroup$












  • $begingroup$
    What is maneuverability?
    $endgroup$
    – William Elliot
    Jan 20 at 0:10










  • $begingroup$
    reflexivity @WilliamElliot
    $endgroup$
    – VirtualUser
    Jan 20 at 0:38














1












1








1





$begingroup$


I have problem with this task:

Proof that $$ 1_A cup s cdot s cdot s $$ is equivalence relation

where $r subset A times A$ and $r$ is a relation such that
$$ forall_{x,y,z} r(x,y) wedge r(x,z) rightarrow r(y,z) $$ and
$$ s = r cup r^{-1} $$



Reflexivity results directly from the definition and symmetry results from the symmetry of the relationship $s$. This part was not difficult for me, but I am trying to show that this relation is transitive and I have no idea how to show that...










share|cite|improve this question











$endgroup$




I have problem with this task:

Proof that $$ 1_A cup s cdot s cdot s $$ is equivalence relation

where $r subset A times A$ and $r$ is a relation such that
$$ forall_{x,y,z} r(x,y) wedge r(x,z) rightarrow r(y,z) $$ and
$$ s = r cup r^{-1} $$



Reflexivity results directly from the definition and symmetry results from the symmetry of the relationship $s$. This part was not difficult for me, but I am trying to show that this relation is transitive and I have no idea how to show that...







proof-writing relations equivalence-relations






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edited Jan 21 at 22:32







VirtualUser

















asked Jan 19 at 19:01









VirtualUserVirtualUser

865114




865114












  • $begingroup$
    What is maneuverability?
    $endgroup$
    – William Elliot
    Jan 20 at 0:10










  • $begingroup$
    reflexivity @WilliamElliot
    $endgroup$
    – VirtualUser
    Jan 20 at 0:38


















  • $begingroup$
    What is maneuverability?
    $endgroup$
    – William Elliot
    Jan 20 at 0:10










  • $begingroup$
    reflexivity @WilliamElliot
    $endgroup$
    – VirtualUser
    Jan 20 at 0:38
















$begingroup$
What is maneuverability?
$endgroup$
– William Elliot
Jan 20 at 0:10




$begingroup$
What is maneuverability?
$endgroup$
– William Elliot
Jan 20 at 0:10












$begingroup$
reflexivity @WilliamElliot
$endgroup$
– VirtualUser
Jan 20 at 0:38




$begingroup$
reflexivity @WilliamElliot
$endgroup$
– VirtualUser
Jan 20 at 0:38










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Let R be a reflexive, symmetrical relation with six elements in a chain: xRa, aRb, bRz, zRc, cRd, dRz.

Thus R = S and $1_A$ $cup$ S•S•S is not transitive

where A = { x,a,b,y,c,d,z }






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    $begingroup$

    Let R be a reflexive, symmetrical relation with six elements in a chain: xRa, aRb, bRz, zRc, cRd, dRz.

    Thus R = S and $1_A$ $cup$ S•S•S is not transitive

    where A = { x,a,b,y,c,d,z }






    share|cite|improve this answer











    $endgroup$


















      1












      $begingroup$

      Let R be a reflexive, symmetrical relation with six elements in a chain: xRa, aRb, bRz, zRc, cRd, dRz.

      Thus R = S and $1_A$ $cup$ S•S•S is not transitive

      where A = { x,a,b,y,c,d,z }






      share|cite|improve this answer











      $endgroup$
















        1












        1








        1





        $begingroup$

        Let R be a reflexive, symmetrical relation with six elements in a chain: xRa, aRb, bRz, zRc, cRd, dRz.

        Thus R = S and $1_A$ $cup$ S•S•S is not transitive

        where A = { x,a,b,y,c,d,z }






        share|cite|improve this answer











        $endgroup$



        Let R be a reflexive, symmetrical relation with six elements in a chain: xRa, aRb, bRz, zRc, cRd, dRz.

        Thus R = S and $1_A$ $cup$ S•S•S is not transitive

        where A = { x,a,b,y,c,d,z }







        share|cite|improve this answer














        share|cite|improve this answer



        share|cite|improve this answer








        edited Jan 23 at 22:42

























        answered Jan 22 at 22:21









        William ElliotWilliam Elliot

        8,1622720




        8,1622720






























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