Why does this relation fail symmetry and transitivity properties?Properties of Relations. Reflexive,...

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Why does this relation fail symmetry and transitivity properties?


Properties of Relations. Reflexive, Symmetric, and Transitive.$beta$ as the relation “is a brother of”Smallest relation for reflexive, symmetry and transitivityProving Reflexivity, Symmetry and Transitivity of a RelationProving symmetry and transitivityWhy $yC_1x iff yC_2x$ implies $C_1 = C_2$? $C_i$ is a relation.Equivalence relation and partitions.Commutative pairs of relations do not define an equivalence relationProof of transitivity for equivalence relationDoes symmetry and transitivity imply reflexivity for nonempty binary relation?













3












$begingroup$


The question states, let $S$ be the set of all humans.
Define $a ∼ b$ iff $a$ is a full-brother
of $b$.

Symmetry: Since $a$ shares both parents with $b$, then $b$ shares both parents with $a$. Would this be false because $b$ is not defined as a male, so $b$ is instead the full sister of $a$?

Transitivity: Since $a$ shares both parents with $b$, and $b$ shares both parents with $c$, then a shares both parents with $c$. What does the $c$ mean in this context? Is it simply another person introduced?










share|cite|improve this question











$endgroup$

















    3












    $begingroup$


    The question states, let $S$ be the set of all humans.
    Define $a ∼ b$ iff $a$ is a full-brother
    of $b$.

    Symmetry: Since $a$ shares both parents with $b$, then $b$ shares both parents with $a$. Would this be false because $b$ is not defined as a male, so $b$ is instead the full sister of $a$?

    Transitivity: Since $a$ shares both parents with $b$, and $b$ shares both parents with $c$, then a shares both parents with $c$. What does the $c$ mean in this context? Is it simply another person introduced?










    share|cite|improve this question











    $endgroup$















      3












      3








      3





      $begingroup$


      The question states, let $S$ be the set of all humans.
      Define $a ∼ b$ iff $a$ is a full-brother
      of $b$.

      Symmetry: Since $a$ shares both parents with $b$, then $b$ shares both parents with $a$. Would this be false because $b$ is not defined as a male, so $b$ is instead the full sister of $a$?

      Transitivity: Since $a$ shares both parents with $b$, and $b$ shares both parents with $c$, then a shares both parents with $c$. What does the $c$ mean in this context? Is it simply another person introduced?










      share|cite|improve this question











      $endgroup$




      The question states, let $S$ be the set of all humans.
      Define $a ∼ b$ iff $a$ is a full-brother
      of $b$.

      Symmetry: Since $a$ shares both parents with $b$, then $b$ shares both parents with $a$. Would this be false because $b$ is not defined as a male, so $b$ is instead the full sister of $a$?

      Transitivity: Since $a$ shares both parents with $b$, and $b$ shares both parents with $c$, then a shares both parents with $c$. What does the $c$ mean in this context? Is it simply another person introduced?







      discrete-mathematics relations equivalence-relations






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited 18 mins ago







      Michael Ramage

















      asked 40 mins ago









      Michael RamageMichael Ramage

      234




      234






















          3 Answers
          3






          active

          oldest

          votes


















          1












          $begingroup$

          For a relation to be equvalence relation you also need reflexivity that is
          $$
          asim a, qquad forall a in S.
          $$

          which would mean that $a$ is a full brother of himself which is absurd.



          Reflecting on your other questions if you define $sim$ to be brothership then you definitely run into trouble with different sexes. So in case of $a$ and $b$ has different sex it is not holding up.



          For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up.



          I hope I could help






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            This helps. Thank you! I am trying to figure out why the back of the book states that all properties fail for this relation. Perhaps it is a type. I have seen a few along my journey through it.
            $endgroup$
            – Michael Ramage
            26 mins ago










          • $begingroup$
            " For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up" it fails if a and c are the same person.
            $endgroup$
            – fleablood
            47 secs ago



















          4












          $begingroup$

          I am a full brother of my sister, but my sister is not a full brother of me. So this relation is not symmetric.



          Transitivity is true though. If $a$ is a full brother of $b$ and $b$ is a full brother of $c$, then $a$ is a full brother of $c$.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            ... and yes, in this case $c$ is just a third person introduced.
            $endgroup$
            – Arthur
            31 mins ago












          • $begingroup$
            Since a is a full brother of b and b is a full brother of c means that both a and b are males, so c can be a sister to a and b. Even in that case, a is the brother of c. However, the back of my book says that all properties fail. I do not know if this is a type or not. Thank you both!
            $endgroup$
            – Michael Ramage
            28 mins ago










          • $begingroup$
            " Transitivity is true though. If a is a full brother of b and b is a full brother of c , then is a full brother of a". Not if a and c are the same person! Transitivity fails.
            $endgroup$
            – fleablood
            3 mins ago





















          0












          $begingroup$

          Your title is inaccurate. An equivalence relationship can't fail symmetric and transitive properties, by definition, and this is not an equivalence relation because it does fail.



          It fails reflexive because $a $~$a $ never happens. No-one is their own brother.



          It fails symmetry for exactly the reason you state. If Allen, a boy, and Betty, girl, have the same parents than Allen is a full brother to Betty, but Betty is not a full brother to Allen.



          Update!



          Transitivity fails. If Allen is a full brother to Bob. And Bob is a full brother to Allen then Allen is not a full brother to Allen.



          Transitivity fails.



          ===



          I suppose we can define $a $~$b $ as 1) $a $ and be have the same parents, 2) $a $ is male, 3) $a $ and $b $ are different people.



          Since no-one can 3) be a different person than oneself reflexivity can never happen. 2)Also being male may or may not occur. But 1) have same parents as self must always occur.



          If $a $~$b $ then 1) $b$ and $a $ have same parents and 3) $b $






          share|cite|improve this answer











          $endgroup$













          • $begingroup$
            I have corrected it. Does it read correct now?
            $endgroup$
            – Michael Ramage
            17 mins ago










          • $begingroup$
            Yes. it's a relation. But it's not an equivalence relation. It's not an equivalence relation because it fails. BTW I don't know why your book says transitivity fails.
            $endgroup$
            – fleablood
            15 mins ago










          • $begingroup$
            I understand. It is a book by my professor Alex McCallister, "A Transition to Advanced Mathematics: A Survey Course." I have spent several hours attempting to understand why transitivity fails, when it does not, unfortunately.
            $endgroup$
            – Michael Ramage
            12 mins ago












          • $begingroup$
            Got it! If $a$ and $b $ are both boys then $a=b$ and $b=a$ but $ane a$.
            $endgroup$
            – fleablood
            4 mins ago











          Your Answer





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          3 Answers
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          active

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          3 Answers
          3






          active

          oldest

          votes









          active

          oldest

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          active

          oldest

          votes









          1












          $begingroup$

          For a relation to be equvalence relation you also need reflexivity that is
          $$
          asim a, qquad forall a in S.
          $$

          which would mean that $a$ is a full brother of himself which is absurd.



          Reflecting on your other questions if you define $sim$ to be brothership then you definitely run into trouble with different sexes. So in case of $a$ and $b$ has different sex it is not holding up.



          For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up.



          I hope I could help






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            This helps. Thank you! I am trying to figure out why the back of the book states that all properties fail for this relation. Perhaps it is a type. I have seen a few along my journey through it.
            $endgroup$
            – Michael Ramage
            26 mins ago










          • $begingroup$
            " For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up" it fails if a and c are the same person.
            $endgroup$
            – fleablood
            47 secs ago
















          1












          $begingroup$

          For a relation to be equvalence relation you also need reflexivity that is
          $$
          asim a, qquad forall a in S.
          $$

          which would mean that $a$ is a full brother of himself which is absurd.



          Reflecting on your other questions if you define $sim$ to be brothership then you definitely run into trouble with different sexes. So in case of $a$ and $b$ has different sex it is not holding up.



          For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up.



          I hope I could help






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            This helps. Thank you! I am trying to figure out why the back of the book states that all properties fail for this relation. Perhaps it is a type. I have seen a few along my journey through it.
            $endgroup$
            – Michael Ramage
            26 mins ago










          • $begingroup$
            " For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up" it fails if a and c are the same person.
            $endgroup$
            – fleablood
            47 secs ago














          1












          1








          1





          $begingroup$

          For a relation to be equvalence relation you also need reflexivity that is
          $$
          asim a, qquad forall a in S.
          $$

          which would mean that $a$ is a full brother of himself which is absurd.



          Reflecting on your other questions if you define $sim$ to be brothership then you definitely run into trouble with different sexes. So in case of $a$ and $b$ has different sex it is not holding up.



          For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up.



          I hope I could help






          share|cite|improve this answer









          $endgroup$



          For a relation to be equvalence relation you also need reflexivity that is
          $$
          asim a, qquad forall a in S.
          $$

          which would mean that $a$ is a full brother of himself which is absurd.



          Reflecting on your other questions if you define $sim$ to be brothership then you definitely run into trouble with different sexes. So in case of $a$ and $b$ has different sex it is not holding up.



          For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up.



          I hope I could help







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered 29 mins ago









          Vinyl_coat_jawaVinyl_coat_jawa

          2,9651130




          2,9651130












          • $begingroup$
            This helps. Thank you! I am trying to figure out why the back of the book states that all properties fail for this relation. Perhaps it is a type. I have seen a few along my journey through it.
            $endgroup$
            – Michael Ramage
            26 mins ago










          • $begingroup$
            " For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up" it fails if a and c are the same person.
            $endgroup$
            – fleablood
            47 secs ago


















          • $begingroup$
            This helps. Thank you! I am trying to figure out why the back of the book states that all properties fail for this relation. Perhaps it is a type. I have seen a few along my journey through it.
            $endgroup$
            – Michael Ramage
            26 mins ago










          • $begingroup$
            " For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up" it fails if a and c are the same person.
            $endgroup$
            – fleablood
            47 secs ago
















          $begingroup$
          This helps. Thank you! I am trying to figure out why the back of the book states that all properties fail for this relation. Perhaps it is a type. I have seen a few along my journey through it.
          $endgroup$
          – Michael Ramage
          26 mins ago




          $begingroup$
          This helps. Thank you! I am trying to figure out why the back of the book states that all properties fail for this relation. Perhaps it is a type. I have seen a few along my journey through it.
          $endgroup$
          – Michael Ramage
          26 mins ago












          $begingroup$
          " For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up" it fails if a and c are the same person.
          $endgroup$
          – fleablood
          47 secs ago




          $begingroup$
          " For the question about transitivity you would read, "a is a full brother of b" and "b is a full brother of c". I would say that this holds up" it fails if a and c are the same person.
          $endgroup$
          – fleablood
          47 secs ago











          4












          $begingroup$

          I am a full brother of my sister, but my sister is not a full brother of me. So this relation is not symmetric.



          Transitivity is true though. If $a$ is a full brother of $b$ and $b$ is a full brother of $c$, then $a$ is a full brother of $c$.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            ... and yes, in this case $c$ is just a third person introduced.
            $endgroup$
            – Arthur
            31 mins ago












          • $begingroup$
            Since a is a full brother of b and b is a full brother of c means that both a and b are males, so c can be a sister to a and b. Even in that case, a is the brother of c. However, the back of my book says that all properties fail. I do not know if this is a type or not. Thank you both!
            $endgroup$
            – Michael Ramage
            28 mins ago










          • $begingroup$
            " Transitivity is true though. If a is a full brother of b and b is a full brother of c , then is a full brother of a". Not if a and c are the same person! Transitivity fails.
            $endgroup$
            – fleablood
            3 mins ago


















          4












          $begingroup$

          I am a full brother of my sister, but my sister is not a full brother of me. So this relation is not symmetric.



          Transitivity is true though. If $a$ is a full brother of $b$ and $b$ is a full brother of $c$, then $a$ is a full brother of $c$.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            ... and yes, in this case $c$ is just a third person introduced.
            $endgroup$
            – Arthur
            31 mins ago












          • $begingroup$
            Since a is a full brother of b and b is a full brother of c means that both a and b are males, so c can be a sister to a and b. Even in that case, a is the brother of c. However, the back of my book says that all properties fail. I do not know if this is a type or not. Thank you both!
            $endgroup$
            – Michael Ramage
            28 mins ago










          • $begingroup$
            " Transitivity is true though. If a is a full brother of b and b is a full brother of c , then is a full brother of a". Not if a and c are the same person! Transitivity fails.
            $endgroup$
            – fleablood
            3 mins ago
















          4












          4








          4





          $begingroup$

          I am a full brother of my sister, but my sister is not a full brother of me. So this relation is not symmetric.



          Transitivity is true though. If $a$ is a full brother of $b$ and $b$ is a full brother of $c$, then $a$ is a full brother of $c$.






          share|cite|improve this answer









          $endgroup$



          I am a full brother of my sister, but my sister is not a full brother of me. So this relation is not symmetric.



          Transitivity is true though. If $a$ is a full brother of $b$ and $b$ is a full brother of $c$, then $a$ is a full brother of $c$.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered 32 mins ago









          Robert IsraelRobert Israel

          325k23214468




          325k23214468












          • $begingroup$
            ... and yes, in this case $c$ is just a third person introduced.
            $endgroup$
            – Arthur
            31 mins ago












          • $begingroup$
            Since a is a full brother of b and b is a full brother of c means that both a and b are males, so c can be a sister to a and b. Even in that case, a is the brother of c. However, the back of my book says that all properties fail. I do not know if this is a type or not. Thank you both!
            $endgroup$
            – Michael Ramage
            28 mins ago










          • $begingroup$
            " Transitivity is true though. If a is a full brother of b and b is a full brother of c , then is a full brother of a". Not if a and c are the same person! Transitivity fails.
            $endgroup$
            – fleablood
            3 mins ago




















          • $begingroup$
            ... and yes, in this case $c$ is just a third person introduced.
            $endgroup$
            – Arthur
            31 mins ago












          • $begingroup$
            Since a is a full brother of b and b is a full brother of c means that both a and b are males, so c can be a sister to a and b. Even in that case, a is the brother of c. However, the back of my book says that all properties fail. I do not know if this is a type or not. Thank you both!
            $endgroup$
            – Michael Ramage
            28 mins ago










          • $begingroup$
            " Transitivity is true though. If a is a full brother of b and b is a full brother of c , then is a full brother of a". Not if a and c are the same person! Transitivity fails.
            $endgroup$
            – fleablood
            3 mins ago


















          $begingroup$
          ... and yes, in this case $c$ is just a third person introduced.
          $endgroup$
          – Arthur
          31 mins ago






          $begingroup$
          ... and yes, in this case $c$ is just a third person introduced.
          $endgroup$
          – Arthur
          31 mins ago














          $begingroup$
          Since a is a full brother of b and b is a full brother of c means that both a and b are males, so c can be a sister to a and b. Even in that case, a is the brother of c. However, the back of my book says that all properties fail. I do not know if this is a type or not. Thank you both!
          $endgroup$
          – Michael Ramage
          28 mins ago




          $begingroup$
          Since a is a full brother of b and b is a full brother of c means that both a and b are males, so c can be a sister to a and b. Even in that case, a is the brother of c. However, the back of my book says that all properties fail. I do not know if this is a type or not. Thank you both!
          $endgroup$
          – Michael Ramage
          28 mins ago












          $begingroup$
          " Transitivity is true though. If a is a full brother of b and b is a full brother of c , then is a full brother of a". Not if a and c are the same person! Transitivity fails.
          $endgroup$
          – fleablood
          3 mins ago






          $begingroup$
          " Transitivity is true though. If a is a full brother of b and b is a full brother of c , then is a full brother of a". Not if a and c are the same person! Transitivity fails.
          $endgroup$
          – fleablood
          3 mins ago













          0












          $begingroup$

          Your title is inaccurate. An equivalence relationship can't fail symmetric and transitive properties, by definition, and this is not an equivalence relation because it does fail.



          It fails reflexive because $a $~$a $ never happens. No-one is their own brother.



          It fails symmetry for exactly the reason you state. If Allen, a boy, and Betty, girl, have the same parents than Allen is a full brother to Betty, but Betty is not a full brother to Allen.



          Update!



          Transitivity fails. If Allen is a full brother to Bob. And Bob is a full brother to Allen then Allen is not a full brother to Allen.



          Transitivity fails.



          ===



          I suppose we can define $a $~$b $ as 1) $a $ and be have the same parents, 2) $a $ is male, 3) $a $ and $b $ are different people.



          Since no-one can 3) be a different person than oneself reflexivity can never happen. 2)Also being male may or may not occur. But 1) have same parents as self must always occur.



          If $a $~$b $ then 1) $b$ and $a $ have same parents and 3) $b $






          share|cite|improve this answer











          $endgroup$













          • $begingroup$
            I have corrected it. Does it read correct now?
            $endgroup$
            – Michael Ramage
            17 mins ago










          • $begingroup$
            Yes. it's a relation. But it's not an equivalence relation. It's not an equivalence relation because it fails. BTW I don't know why your book says transitivity fails.
            $endgroup$
            – fleablood
            15 mins ago










          • $begingroup$
            I understand. It is a book by my professor Alex McCallister, "A Transition to Advanced Mathematics: A Survey Course." I have spent several hours attempting to understand why transitivity fails, when it does not, unfortunately.
            $endgroup$
            – Michael Ramage
            12 mins ago












          • $begingroup$
            Got it! If $a$ and $b $ are both boys then $a=b$ and $b=a$ but $ane a$.
            $endgroup$
            – fleablood
            4 mins ago
















          0












          $begingroup$

          Your title is inaccurate. An equivalence relationship can't fail symmetric and transitive properties, by definition, and this is not an equivalence relation because it does fail.



          It fails reflexive because $a $~$a $ never happens. No-one is their own brother.



          It fails symmetry for exactly the reason you state. If Allen, a boy, and Betty, girl, have the same parents than Allen is a full brother to Betty, but Betty is not a full brother to Allen.



          Update!



          Transitivity fails. If Allen is a full brother to Bob. And Bob is a full brother to Allen then Allen is not a full brother to Allen.



          Transitivity fails.



          ===



          I suppose we can define $a $~$b $ as 1) $a $ and be have the same parents, 2) $a $ is male, 3) $a $ and $b $ are different people.



          Since no-one can 3) be a different person than oneself reflexivity can never happen. 2)Also being male may or may not occur. But 1) have same parents as self must always occur.



          If $a $~$b $ then 1) $b$ and $a $ have same parents and 3) $b $






          share|cite|improve this answer











          $endgroup$













          • $begingroup$
            I have corrected it. Does it read correct now?
            $endgroup$
            – Michael Ramage
            17 mins ago










          • $begingroup$
            Yes. it's a relation. But it's not an equivalence relation. It's not an equivalence relation because it fails. BTW I don't know why your book says transitivity fails.
            $endgroup$
            – fleablood
            15 mins ago










          • $begingroup$
            I understand. It is a book by my professor Alex McCallister, "A Transition to Advanced Mathematics: A Survey Course." I have spent several hours attempting to understand why transitivity fails, when it does not, unfortunately.
            $endgroup$
            – Michael Ramage
            12 mins ago












          • $begingroup$
            Got it! If $a$ and $b $ are both boys then $a=b$ and $b=a$ but $ane a$.
            $endgroup$
            – fleablood
            4 mins ago














          0












          0








          0





          $begingroup$

          Your title is inaccurate. An equivalence relationship can't fail symmetric and transitive properties, by definition, and this is not an equivalence relation because it does fail.



          It fails reflexive because $a $~$a $ never happens. No-one is their own brother.



          It fails symmetry for exactly the reason you state. If Allen, a boy, and Betty, girl, have the same parents than Allen is a full brother to Betty, but Betty is not a full brother to Allen.



          Update!



          Transitivity fails. If Allen is a full brother to Bob. And Bob is a full brother to Allen then Allen is not a full brother to Allen.



          Transitivity fails.



          ===



          I suppose we can define $a $~$b $ as 1) $a $ and be have the same parents, 2) $a $ is male, 3) $a $ and $b $ are different people.



          Since no-one can 3) be a different person than oneself reflexivity can never happen. 2)Also being male may or may not occur. But 1) have same parents as self must always occur.



          If $a $~$b $ then 1) $b$ and $a $ have same parents and 3) $b $






          share|cite|improve this answer











          $endgroup$



          Your title is inaccurate. An equivalence relationship can't fail symmetric and transitive properties, by definition, and this is not an equivalence relation because it does fail.



          It fails reflexive because $a $~$a $ never happens. No-one is their own brother.



          It fails symmetry for exactly the reason you state. If Allen, a boy, and Betty, girl, have the same parents than Allen is a full brother to Betty, but Betty is not a full brother to Allen.



          Update!



          Transitivity fails. If Allen is a full brother to Bob. And Bob is a full brother to Allen then Allen is not a full brother to Allen.



          Transitivity fails.



          ===



          I suppose we can define $a $~$b $ as 1) $a $ and be have the same parents, 2) $a $ is male, 3) $a $ and $b $ are different people.



          Since no-one can 3) be a different person than oneself reflexivity can never happen. 2)Also being male may or may not occur. But 1) have same parents as self must always occur.



          If $a $~$b $ then 1) $b$ and $a $ have same parents and 3) $b $







          share|cite|improve this answer














          share|cite|improve this answer



          share|cite|improve this answer








          edited 6 mins ago

























          answered 19 mins ago









          fleabloodfleablood

          71.4k22686




          71.4k22686












          • $begingroup$
            I have corrected it. Does it read correct now?
            $endgroup$
            – Michael Ramage
            17 mins ago










          • $begingroup$
            Yes. it's a relation. But it's not an equivalence relation. It's not an equivalence relation because it fails. BTW I don't know why your book says transitivity fails.
            $endgroup$
            – fleablood
            15 mins ago










          • $begingroup$
            I understand. It is a book by my professor Alex McCallister, "A Transition to Advanced Mathematics: A Survey Course." I have spent several hours attempting to understand why transitivity fails, when it does not, unfortunately.
            $endgroup$
            – Michael Ramage
            12 mins ago












          • $begingroup$
            Got it! If $a$ and $b $ are both boys then $a=b$ and $b=a$ but $ane a$.
            $endgroup$
            – fleablood
            4 mins ago


















          • $begingroup$
            I have corrected it. Does it read correct now?
            $endgroup$
            – Michael Ramage
            17 mins ago










          • $begingroup$
            Yes. it's a relation. But it's not an equivalence relation. It's not an equivalence relation because it fails. BTW I don't know why your book says transitivity fails.
            $endgroup$
            – fleablood
            15 mins ago










          • $begingroup$
            I understand. It is a book by my professor Alex McCallister, "A Transition to Advanced Mathematics: A Survey Course." I have spent several hours attempting to understand why transitivity fails, when it does not, unfortunately.
            $endgroup$
            – Michael Ramage
            12 mins ago












          • $begingroup$
            Got it! If $a$ and $b $ are both boys then $a=b$ and $b=a$ but $ane a$.
            $endgroup$
            – fleablood
            4 mins ago
















          $begingroup$
          I have corrected it. Does it read correct now?
          $endgroup$
          – Michael Ramage
          17 mins ago




          $begingroup$
          I have corrected it. Does it read correct now?
          $endgroup$
          – Michael Ramage
          17 mins ago












          $begingroup$
          Yes. it's a relation. But it's not an equivalence relation. It's not an equivalence relation because it fails. BTW I don't know why your book says transitivity fails.
          $endgroup$
          – fleablood
          15 mins ago




          $begingroup$
          Yes. it's a relation. But it's not an equivalence relation. It's not an equivalence relation because it fails. BTW I don't know why your book says transitivity fails.
          $endgroup$
          – fleablood
          15 mins ago












          $begingroup$
          I understand. It is a book by my professor Alex McCallister, "A Transition to Advanced Mathematics: A Survey Course." I have spent several hours attempting to understand why transitivity fails, when it does not, unfortunately.
          $endgroup$
          – Michael Ramage
          12 mins ago






          $begingroup$
          I understand. It is a book by my professor Alex McCallister, "A Transition to Advanced Mathematics: A Survey Course." I have spent several hours attempting to understand why transitivity fails, when it does not, unfortunately.
          $endgroup$
          – Michael Ramage
          12 mins ago














          $begingroup$
          Got it! If $a$ and $b $ are both boys then $a=b$ and $b=a$ but $ane a$.
          $endgroup$
          – fleablood
          4 mins ago




          $begingroup$
          Got it! If $a$ and $b $ are both boys then $a=b$ and $b=a$ but $ane a$.
          $endgroup$
          – fleablood
          4 mins ago


















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