Exercise 4.11 Allufi












1














This exercise is on page 69 of Algebra chapter 0.



Problem:




In due time we will prove the easy fact that if $p$ is a prime integer, then the equation $x^d = 1$ can have at most $d$ solutions in $mathbb{Z}/pmathbb{Z}$. Assume this fact, and prove that the multiplicative group $G =(mathbb{Z}/pmathbb{Z})^{ast}$ is cyclic.




Attempt:



Using the this fact along with another exercise one can show that $h^{|g|} = 1$ for $g in G$ element of maximal order. This shows that for all $|h| leq |g|$ for all $h in G$. We can also show that $|g| leq |G| = p - 1$.
I am not sure how can we show that $|G| leq |g|$ though ? I don't want to use Lagrange theorem as we don't know this result yet in the book.










share|cite|improve this question
























  • See this question.
    – Dietrich Burde
    Dec 26 '18 at 20:51










  • See this theorem.
    – Bill Dubuque
    Dec 27 '18 at 2:23
















1














This exercise is on page 69 of Algebra chapter 0.



Problem:




In due time we will prove the easy fact that if $p$ is a prime integer, then the equation $x^d = 1$ can have at most $d$ solutions in $mathbb{Z}/pmathbb{Z}$. Assume this fact, and prove that the multiplicative group $G =(mathbb{Z}/pmathbb{Z})^{ast}$ is cyclic.




Attempt:



Using the this fact along with another exercise one can show that $h^{|g|} = 1$ for $g in G$ element of maximal order. This shows that for all $|h| leq |g|$ for all $h in G$. We can also show that $|g| leq |G| = p - 1$.
I am not sure how can we show that $|G| leq |g|$ though ? I don't want to use Lagrange theorem as we don't know this result yet in the book.










share|cite|improve this question
























  • See this question.
    – Dietrich Burde
    Dec 26 '18 at 20:51










  • See this theorem.
    – Bill Dubuque
    Dec 27 '18 at 2:23














1












1








1







This exercise is on page 69 of Algebra chapter 0.



Problem:




In due time we will prove the easy fact that if $p$ is a prime integer, then the equation $x^d = 1$ can have at most $d$ solutions in $mathbb{Z}/pmathbb{Z}$. Assume this fact, and prove that the multiplicative group $G =(mathbb{Z}/pmathbb{Z})^{ast}$ is cyclic.




Attempt:



Using the this fact along with another exercise one can show that $h^{|g|} = 1$ for $g in G$ element of maximal order. This shows that for all $|h| leq |g|$ for all $h in G$. We can also show that $|g| leq |G| = p - 1$.
I am not sure how can we show that $|G| leq |g|$ though ? I don't want to use Lagrange theorem as we don't know this result yet in the book.










share|cite|improve this question















This exercise is on page 69 of Algebra chapter 0.



Problem:




In due time we will prove the easy fact that if $p$ is a prime integer, then the equation $x^d = 1$ can have at most $d$ solutions in $mathbb{Z}/pmathbb{Z}$. Assume this fact, and prove that the multiplicative group $G =(mathbb{Z}/pmathbb{Z})^{ast}$ is cyclic.




Attempt:



Using the this fact along with another exercise one can show that $h^{|g|} = 1$ for $g in G$ element of maximal order. This shows that for all $|h| leq |g|$ for all $h in G$. We can also show that $|g| leq |G| = p - 1$.
I am not sure how can we show that $|G| leq |g|$ though ? I don't want to use Lagrange theorem as we don't know this result yet in the book.







abstract-algebra group-theory polynomials cyclic-groups






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 27 '18 at 0:56









the_fox

2,43411431




2,43411431










asked Dec 26 '18 at 20:37









Newbie

426211




426211












  • See this question.
    – Dietrich Burde
    Dec 26 '18 at 20:51










  • See this theorem.
    – Bill Dubuque
    Dec 27 '18 at 2:23


















  • See this question.
    – Dietrich Burde
    Dec 26 '18 at 20:51










  • See this theorem.
    – Bill Dubuque
    Dec 27 '18 at 2:23
















See this question.
– Dietrich Burde
Dec 26 '18 at 20:51




See this question.
– Dietrich Burde
Dec 26 '18 at 20:51












See this theorem.
– Bill Dubuque
Dec 27 '18 at 2:23




See this theorem.
– Bill Dubuque
Dec 27 '18 at 2:23










1 Answer
1






active

oldest

votes


















1














If $mid gmidlt mid Gmid=p-1$, then $x^{mid gmid}=1$ has $p-1gtmid gmid$ solutions. This contradicts the fact you were given about $x^d=1$.






share|cite|improve this answer





















    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%2f3053297%2fexercise-4-11-allufi%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    1














    If $mid gmidlt mid Gmid=p-1$, then $x^{mid gmid}=1$ has $p-1gtmid gmid$ solutions. This contradicts the fact you were given about $x^d=1$.






    share|cite|improve this answer


























      1














      If $mid gmidlt mid Gmid=p-1$, then $x^{mid gmid}=1$ has $p-1gtmid gmid$ solutions. This contradicts the fact you were given about $x^d=1$.






      share|cite|improve this answer
























        1












        1








        1






        If $mid gmidlt mid Gmid=p-1$, then $x^{mid gmid}=1$ has $p-1gtmid gmid$ solutions. This contradicts the fact you were given about $x^d=1$.






        share|cite|improve this answer












        If $mid gmidlt mid Gmid=p-1$, then $x^{mid gmid}=1$ has $p-1gtmid gmid$ solutions. This contradicts the fact you were given about $x^d=1$.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Dec 27 '18 at 4:10









        Chris Custer

        10.8k3824




        10.8k3824






























            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.





            Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


            Please pay close attention to the following guidance:


            • 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.


            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%2f3053297%2fexercise-4-11-allufi%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

            Human spaceflight

            Can not write log (Is /dev/pts mounted?) - openpty in Ubuntu-on-Windows?

            File:DeusFollowingSea.jpg