Abelian groups about rationalsExact sequence of abelian groups, property transfersNon-Abelian groups and subgroupsIn direct products of $n$ groups, do we also prove conditions for a group to be abelian or not?Question about finitely generated abelian groupsQuestion about Finite Abelian GroupsAbstract Algebra. Let $mathitG $ be an abelian group. Show that the elements of finite order in $mathitG$ form a subgroup of $mathitG$.True or false simple algebra questions (centralizers, conjugacy classes, normal groups, abelian groups)Abelian groups of odd orderAbelian Group of Rationals over addition - axiomatic or derived?Showing there is a unique group table for $1, a,b,c$ such that there is no element of order $4$.

Creating a loop after a break using Markov Chain in Tikz

Is a vector space a subspace of itself?

Map list to bin numbers

How is it possible for user's password to be changed after storage was encrypted? (on OS X, Android)

If a centaur druid Wild Shapes into a Giant Elk, do their Charge features stack?

Crop image to path created in TikZ?

Information to fellow intern about hiring?

How can I fix this gap between bookcases I made?

Are objects structures and/or vice versa?

Is every set a filtered colimit of finite sets?

What is the meaning of "of trouble" in the following sentence?

Why is my log file so massive? 22gb. I am running log backups

Why airport relocation isn't done gradually?

Denied boarding due to overcrowding, Sparpreis ticket. What are my rights?

Doomsday-clock for my fantasy planet

Is there a name of the flying bionic bird?

Re-submission of rejected manuscript without informing co-authors

How to answer pointed "are you quitting" questioning when I don't want them to suspect

What is the offset in a seaplane's hull?

Is domain driven design an anti-SQL pattern?

Is there a familial term for apples and pears?

LWC and complex parameters

How to make payment on the internet without leaving a money trail?

Is this food a bread or a loaf?



Abelian groups about rationals


Exact sequence of abelian groups, property transfersNon-Abelian groups and subgroupsIn direct products of $n$ groups, do we also prove conditions for a group to be abelian or not?Question about finitely generated abelian groupsQuestion about Finite Abelian GroupsAbstract Algebra. Let $mathitG $ be an abelian group. Show that the elements of finite order in $mathitG$ form a subgroup of $mathitG$.True or false simple algebra questions (centralizers, conjugacy classes, normal groups, abelian groups)Abelian groups of odd orderAbelian Group of Rationals over addition - axiomatic or derived?Showing there is a unique group table for $1, a,b,c$ such that there is no element of order $4$.













2












$begingroup$


Is the set $mathbbQ$ under $×$ an abelian group? It is sure for $mathbbQ - 0$, but i think the whole set of rationals is not an abelian group as $0 × a = a × 0 = 0$, but the identity element is $1$ and i think it must be unique, and $a$ is not equal to $0$. Can you please help me whether it is an abelian group under $×$ or not?










share|cite|improve this question











$endgroup$
















    2












    $begingroup$


    Is the set $mathbbQ$ under $×$ an abelian group? It is sure for $mathbbQ - 0$, but i think the whole set of rationals is not an abelian group as $0 × a = a × 0 = 0$, but the identity element is $1$ and i think it must be unique, and $a$ is not equal to $0$. Can you please help me whether it is an abelian group under $×$ or not?










    share|cite|improve this question











    $endgroup$














      2












      2








      2





      $begingroup$


      Is the set $mathbbQ$ under $×$ an abelian group? It is sure for $mathbbQ - 0$, but i think the whole set of rationals is not an abelian group as $0 × a = a × 0 = 0$, but the identity element is $1$ and i think it must be unique, and $a$ is not equal to $0$. Can you please help me whether it is an abelian group under $×$ or not?










      share|cite|improve this question











      $endgroup$




      Is the set $mathbbQ$ under $×$ an abelian group? It is sure for $mathbbQ - 0$, but i think the whole set of rationals is not an abelian group as $0 × a = a × 0 = 0$, but the identity element is $1$ and i think it must be unique, and $a$ is not equal to $0$. Can you please help me whether it is an abelian group under $×$ or not?







      abstract-algebra abelian-groups rational-numbers binary-operations






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Apr 3 at 3:00









      user21820

      40.1k544162




      40.1k544162










      asked Mar 22 at 16:14







      user655794



























          1 Answer
          1






          active

          oldest

          votes


















          5












          $begingroup$

          It is not a group under multiplication, since $0$ has no inverse.






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            Sir i have requested for deletion of my account so i restored everything. Will the question be still there after my account is delete?
            $endgroup$
            – user655794
            Mar 25 at 19:15











          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%2f3158339%2fabelian-groups-about-rationals%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









          5












          $begingroup$

          It is not a group under multiplication, since $0$ has no inverse.






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            Sir i have requested for deletion of my account so i restored everything. Will the question be still there after my account is delete?
            $endgroup$
            – user655794
            Mar 25 at 19:15















          5












          $begingroup$

          It is not a group under multiplication, since $0$ has no inverse.






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            Sir i have requested for deletion of my account so i restored everything. Will the question be still there after my account is delete?
            $endgroup$
            – user655794
            Mar 25 at 19:15













          5












          5








          5





          $begingroup$

          It is not a group under multiplication, since $0$ has no inverse.






          share|cite|improve this answer









          $endgroup$



          It is not a group under multiplication, since $0$ has no inverse.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Mar 22 at 16:15









          José Carlos SantosJosé Carlos Santos

          173k23133241




          173k23133241











          • $begingroup$
            Sir i have requested for deletion of my account so i restored everything. Will the question be still there after my account is delete?
            $endgroup$
            – user655794
            Mar 25 at 19:15
















          • $begingroup$
            Sir i have requested for deletion of my account so i restored everything. Will the question be still there after my account is delete?
            $endgroup$
            – user655794
            Mar 25 at 19:15















          $begingroup$
          Sir i have requested for deletion of my account so i restored everything. Will the question be still there after my account is delete?
          $endgroup$
          – user655794
          Mar 25 at 19:15




          $begingroup$
          Sir i have requested for deletion of my account so i restored everything. Will the question be still there after my account is delete?
          $endgroup$
          – user655794
          Mar 25 at 19:15

















          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%2f3158339%2fabelian-groups-about-rationals%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

          How should I support this large drywall patch? Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern) Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?How do I cover large gaps in drywall?How do I keep drywall around a patch from crumbling?Can I glue a second layer of drywall?How to patch long strip on drywall?Large drywall patch: how to avoid bulging seams?Drywall Mesh Patch vs. Bulge? To remove or not to remove?How to fix this drywall job?Prep drywall before backsplashWhat's the best way to fix this horrible drywall patch job?Drywall patching using 3M Patch Plus Primer

          random experiment with two different functions on unit interval Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern)Random variable and probability space notionsRandom Walk with EdgesFinding functions where the increase over a random interval is Poisson distributedNumber of days until dayCan an observed event in fact be of zero probability?Unit random processmodels of coins and uniform distributionHow to get the number of successes given $n$ trials , probability $P$ and a random variable $X$Absorbing Markov chain in a computer. Is “almost every” turned into always convergence in computer executions?Stopped random walk is not uniformly integrable

          Lowndes Grove History Architecture References Navigation menu32°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661132°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661178002500"National Register Information System"Historic houses of South Carolina"Lowndes Grove""+32° 48' 6.00", −79° 57' 58.00""Lowndes Grove, Charleston County (260 St. Margaret St., Charleston)""Lowndes Grove"The Charleston ExpositionIt Happened in South Carolina"Lowndes Grove (House), Saint Margaret Street & Sixth Avenue, Charleston, Charleston County, SC(Photographs)"Plantations of the Carolina Low Countrye