Prove or disprove this table is a field












2












$begingroup$


enter image description here



Any help will be appreciated on how to approach this and get started.










share|cite|improve this question









$endgroup$








  • 4




    $begingroup$
    Hint: removal of $0$ should yield a group under multiplication.
    $endgroup$
    – Randall
    2 hours ago
















2












$begingroup$


enter image description here



Any help will be appreciated on how to approach this and get started.










share|cite|improve this question









$endgroup$








  • 4




    $begingroup$
    Hint: removal of $0$ should yield a group under multiplication.
    $endgroup$
    – Randall
    2 hours ago














2












2








2


1



$begingroup$


enter image description here



Any help will be appreciated on how to approach this and get started.










share|cite|improve this question









$endgroup$




enter image description here



Any help will be appreciated on how to approach this and get started.







abstract-algebra discrete-mathematics






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked 2 hours ago









Wade KemmsiesWade Kemmsies

263




263








  • 4




    $begingroup$
    Hint: removal of $0$ should yield a group under multiplication.
    $endgroup$
    – Randall
    2 hours ago














  • 4




    $begingroup$
    Hint: removal of $0$ should yield a group under multiplication.
    $endgroup$
    – Randall
    2 hours ago








4




4




$begingroup$
Hint: removal of $0$ should yield a group under multiplication.
$endgroup$
– Randall
2 hours ago




$begingroup$
Hint: removal of $0$ should yield a group under multiplication.
$endgroup$
– Randall
2 hours ago










2 Answers
2






active

oldest

votes


















2












$begingroup$

A field has no non-zero divisors of zero.






share|cite|improve this answer









$endgroup$





















    2












    $begingroup$

    Note from the multiplication table, the one for the $cdot$ operation, that



    $2 cdot 2 = 0; tag 1$



    thus $2$ is nilpotent; but a field $F$ can have no non-zero nilpotents (note $2 ne 0$ since $3 + 2 = 1 ne 3$).



    If $F$ is a field and $a in F$ were nilpotent, that is, if



    $a^k = 0, ; 2 le k in Bbb N, tag 2$



    then



    $a = a^{1 - k} a^k = a^{1 - k} = 0; tag 3$



    which shows a field has no non-zero nilpotent elements.






    share|cite|improve this answer











    $endgroup$









    • 1




      $begingroup$
      Did you mean $a = a^{1-k} a^k = a^{1-k} times 0 =0$ ?
      $endgroup$
      – J. W. Tanner
      19 mins ago












    • $begingroup$
      @J.W.Tanner: yuppers, sure did!
      $endgroup$
      – Robert Lewis
      5 mins ago











    Your Answer





    StackExchange.ifUsing("editor", function () {
    return StackExchange.using("mathjaxEditing", function () {
    StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
    StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
    });
    });
    }, "mathjax-editing");

    StackExchange.ready(function() {
    var channelOptions = {
    tags: "".split(" "),
    id: "69"
    };
    initTagRenderer("".split(" "), "".split(" "), channelOptions);

    StackExchange.using("externalEditor", function() {
    // Have to fire editor after snippets, if snippets enabled
    if (StackExchange.settings.snippets.snippetsEnabled) {
    StackExchange.using("snippets", function() {
    createEditor();
    });
    }
    else {
    createEditor();
    }
    });

    function createEditor() {
    StackExchange.prepareEditor({
    heartbeatType: 'answer',
    autoActivateHeartbeat: false,
    convertImagesToLinks: true,
    noModals: true,
    showLowRepImageUploadWarning: true,
    reputationToPostImages: 10,
    bindNavPrevention: true,
    postfix: "",
    imageUploader: {
    brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
    contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
    allowUrls: true
    },
    noCode: true, onDemand: true,
    discardSelector: ".discard-answer"
    ,immediatelyShowMarkdownHelp:true
    });


    }
    });














    draft saved

    draft discarded


















    StackExchange.ready(
    function () {
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3072800%2fprove-or-disprove-this-table-is-a-field%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    2 Answers
    2






    active

    oldest

    votes








    2 Answers
    2






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    2












    $begingroup$

    A field has no non-zero divisors of zero.






    share|cite|improve this answer









    $endgroup$


















      2












      $begingroup$

      A field has no non-zero divisors of zero.






      share|cite|improve this answer









      $endgroup$
















        2












        2








        2





        $begingroup$

        A field has no non-zero divisors of zero.






        share|cite|improve this answer









        $endgroup$



        A field has no non-zero divisors of zero.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered 2 hours ago









        J. W. TannerJ. W. Tanner

        937




        937























            2












            $begingroup$

            Note from the multiplication table, the one for the $cdot$ operation, that



            $2 cdot 2 = 0; tag 1$



            thus $2$ is nilpotent; but a field $F$ can have no non-zero nilpotents (note $2 ne 0$ since $3 + 2 = 1 ne 3$).



            If $F$ is a field and $a in F$ were nilpotent, that is, if



            $a^k = 0, ; 2 le k in Bbb N, tag 2$



            then



            $a = a^{1 - k} a^k = a^{1 - k} = 0; tag 3$



            which shows a field has no non-zero nilpotent elements.






            share|cite|improve this answer











            $endgroup$









            • 1




              $begingroup$
              Did you mean $a = a^{1-k} a^k = a^{1-k} times 0 =0$ ?
              $endgroup$
              – J. W. Tanner
              19 mins ago












            • $begingroup$
              @J.W.Tanner: yuppers, sure did!
              $endgroup$
              – Robert Lewis
              5 mins ago
















            2












            $begingroup$

            Note from the multiplication table, the one for the $cdot$ operation, that



            $2 cdot 2 = 0; tag 1$



            thus $2$ is nilpotent; but a field $F$ can have no non-zero nilpotents (note $2 ne 0$ since $3 + 2 = 1 ne 3$).



            If $F$ is a field and $a in F$ were nilpotent, that is, if



            $a^k = 0, ; 2 le k in Bbb N, tag 2$



            then



            $a = a^{1 - k} a^k = a^{1 - k} = 0; tag 3$



            which shows a field has no non-zero nilpotent elements.






            share|cite|improve this answer











            $endgroup$









            • 1




              $begingroup$
              Did you mean $a = a^{1-k} a^k = a^{1-k} times 0 =0$ ?
              $endgroup$
              – J. W. Tanner
              19 mins ago












            • $begingroup$
              @J.W.Tanner: yuppers, sure did!
              $endgroup$
              – Robert Lewis
              5 mins ago














            2












            2








            2





            $begingroup$

            Note from the multiplication table, the one for the $cdot$ operation, that



            $2 cdot 2 = 0; tag 1$



            thus $2$ is nilpotent; but a field $F$ can have no non-zero nilpotents (note $2 ne 0$ since $3 + 2 = 1 ne 3$).



            If $F$ is a field and $a in F$ were nilpotent, that is, if



            $a^k = 0, ; 2 le k in Bbb N, tag 2$



            then



            $a = a^{1 - k} a^k = a^{1 - k} = 0; tag 3$



            which shows a field has no non-zero nilpotent elements.






            share|cite|improve this answer











            $endgroup$



            Note from the multiplication table, the one for the $cdot$ operation, that



            $2 cdot 2 = 0; tag 1$



            thus $2$ is nilpotent; but a field $F$ can have no non-zero nilpotents (note $2 ne 0$ since $3 + 2 = 1 ne 3$).



            If $F$ is a field and $a in F$ were nilpotent, that is, if



            $a^k = 0, ; 2 le k in Bbb N, tag 2$



            then



            $a = a^{1 - k} a^k = a^{1 - k} = 0; tag 3$



            which shows a field has no non-zero nilpotent elements.







            share|cite|improve this answer














            share|cite|improve this answer



            share|cite|improve this answer








            edited 2 hours ago

























            answered 2 hours ago









            Robert LewisRobert Lewis

            44.5k22964




            44.5k22964








            • 1




              $begingroup$
              Did you mean $a = a^{1-k} a^k = a^{1-k} times 0 =0$ ?
              $endgroup$
              – J. W. Tanner
              19 mins ago












            • $begingroup$
              @J.W.Tanner: yuppers, sure did!
              $endgroup$
              – Robert Lewis
              5 mins ago














            • 1




              $begingroup$
              Did you mean $a = a^{1-k} a^k = a^{1-k} times 0 =0$ ?
              $endgroup$
              – J. W. Tanner
              19 mins ago












            • $begingroup$
              @J.W.Tanner: yuppers, sure did!
              $endgroup$
              – Robert Lewis
              5 mins ago








            1




            1




            $begingroup$
            Did you mean $a = a^{1-k} a^k = a^{1-k} times 0 =0$ ?
            $endgroup$
            – J. W. Tanner
            19 mins ago






            $begingroup$
            Did you mean $a = a^{1-k} a^k = a^{1-k} times 0 =0$ ?
            $endgroup$
            – J. W. Tanner
            19 mins ago














            $begingroup$
            @J.W.Tanner: yuppers, sure did!
            $endgroup$
            – Robert Lewis
            5 mins ago




            $begingroup$
            @J.W.Tanner: yuppers, sure did!
            $endgroup$
            – Robert Lewis
            5 mins ago


















            draft saved

            draft discarded




















































            Thanks for contributing an answer to Mathematics Stack Exchange!


            • Please be sure to answer the question. Provide details and share your research!

            But avoid



            • Asking for help, clarification, or responding to other answers.

            • Making statements based on opinion; back them up with references or personal experience.


            Use MathJax to format equations. MathJax reference.


            To learn more, see our tips on writing great answers.




            draft saved


            draft discarded














            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3072800%2fprove-or-disprove-this-table-is-a-field%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown





















































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown

































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown







            Popular posts from this blog

            Eastern Orthodox Church

            Zagreb

            Understanding the information contained in the Deep Space Network XML data?