Let $G$ be a finite abelian group with identity $e$. Prove that $exists$ an element $x in G$ such that ord y...












0












$begingroup$


My attempt:



I think somehow we have to show that if $|x|=operatorname{lcm}{|x_i|: x_i in G}$ (as the group is finite abelian) then such an element actually lies in $G-{e}$. But I don't know how to show that such an element indeed lies in $G$.



Thanks for any help!










share|cite|improve this question











$endgroup$












  • $begingroup$
    Do you know the structure theorem for finite Abelian groups?
    $endgroup$
    – Lord Shark the Unknown
    Jan 7 at 4:42










  • $begingroup$
    yeah i do know!
    $endgroup$
    – Infinity
    Jan 7 at 4:43






  • 1




    $begingroup$
    This is going to be false in the case that $G={e}$, for the trivial fact that any statement of the form "$exists x in varnothing ....$" is always false.
    $endgroup$
    – MathematicsStudent1122
    Jan 7 at 4:50












  • $begingroup$
    Pick an element of maxmial order ...
    $endgroup$
    – Hagen von Eitzen
    Jan 7 at 5:25
















0












$begingroup$


My attempt:



I think somehow we have to show that if $|x|=operatorname{lcm}{|x_i|: x_i in G}$ (as the group is finite abelian) then such an element actually lies in $G-{e}$. But I don't know how to show that such an element indeed lies in $G$.



Thanks for any help!










share|cite|improve this question











$endgroup$












  • $begingroup$
    Do you know the structure theorem for finite Abelian groups?
    $endgroup$
    – Lord Shark the Unknown
    Jan 7 at 4:42










  • $begingroup$
    yeah i do know!
    $endgroup$
    – Infinity
    Jan 7 at 4:43






  • 1




    $begingroup$
    This is going to be false in the case that $G={e}$, for the trivial fact that any statement of the form "$exists x in varnothing ....$" is always false.
    $endgroup$
    – MathematicsStudent1122
    Jan 7 at 4:50












  • $begingroup$
    Pick an element of maxmial order ...
    $endgroup$
    – Hagen von Eitzen
    Jan 7 at 5:25














0












0








0





$begingroup$


My attempt:



I think somehow we have to show that if $|x|=operatorname{lcm}{|x_i|: x_i in G}$ (as the group is finite abelian) then such an element actually lies in $G-{e}$. But I don't know how to show that such an element indeed lies in $G$.



Thanks for any help!










share|cite|improve this question











$endgroup$




My attempt:



I think somehow we have to show that if $|x|=operatorname{lcm}{|x_i|: x_i in G}$ (as the group is finite abelian) then such an element actually lies in $G-{e}$. But I don't know how to show that such an element indeed lies in $G$.



Thanks for any help!







abstract-algebra group-theory finite-groups






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Jan 9 at 7:12









CHOUDHARY bhim sen

1239




1239










asked Jan 7 at 4:34









InfinityInfinity

321112




321112












  • $begingroup$
    Do you know the structure theorem for finite Abelian groups?
    $endgroup$
    – Lord Shark the Unknown
    Jan 7 at 4:42










  • $begingroup$
    yeah i do know!
    $endgroup$
    – Infinity
    Jan 7 at 4:43






  • 1




    $begingroup$
    This is going to be false in the case that $G={e}$, for the trivial fact that any statement of the form "$exists x in varnothing ....$" is always false.
    $endgroup$
    – MathematicsStudent1122
    Jan 7 at 4:50












  • $begingroup$
    Pick an element of maxmial order ...
    $endgroup$
    – Hagen von Eitzen
    Jan 7 at 5:25


















  • $begingroup$
    Do you know the structure theorem for finite Abelian groups?
    $endgroup$
    – Lord Shark the Unknown
    Jan 7 at 4:42










  • $begingroup$
    yeah i do know!
    $endgroup$
    – Infinity
    Jan 7 at 4:43






  • 1




    $begingroup$
    This is going to be false in the case that $G={e}$, for the trivial fact that any statement of the form "$exists x in varnothing ....$" is always false.
    $endgroup$
    – MathematicsStudent1122
    Jan 7 at 4:50












  • $begingroup$
    Pick an element of maxmial order ...
    $endgroup$
    – Hagen von Eitzen
    Jan 7 at 5:25
















$begingroup$
Do you know the structure theorem for finite Abelian groups?
$endgroup$
– Lord Shark the Unknown
Jan 7 at 4:42




$begingroup$
Do you know the structure theorem for finite Abelian groups?
$endgroup$
– Lord Shark the Unknown
Jan 7 at 4:42












$begingroup$
yeah i do know!
$endgroup$
– Infinity
Jan 7 at 4:43




$begingroup$
yeah i do know!
$endgroup$
– Infinity
Jan 7 at 4:43




1




1




$begingroup$
This is going to be false in the case that $G={e}$, for the trivial fact that any statement of the form "$exists x in varnothing ....$" is always false.
$endgroup$
– MathematicsStudent1122
Jan 7 at 4:50






$begingroup$
This is going to be false in the case that $G={e}$, for the trivial fact that any statement of the form "$exists x in varnothing ....$" is always false.
$endgroup$
– MathematicsStudent1122
Jan 7 at 4:50














$begingroup$
Pick an element of maxmial order ...
$endgroup$
– Hagen von Eitzen
Jan 7 at 5:25




$begingroup$
Pick an element of maxmial order ...
$endgroup$
– Hagen von Eitzen
Jan 7 at 5:25










1 Answer
1






active

oldest

votes


















1












$begingroup$

If $G = bigoplus_{1 leq i leq k} mathbb{Z}_{n_i}$ with $n_i | n_{i+1}$, consider the element $(0,0, cdots ,1)$ with order $n_k$. It is clear that $exp G = n_k$.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Ah okay..Thanks!
    $endgroup$
    – Infinity
    Jan 7 at 4:52











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%2f3064662%2flet-g-be-a-finite-abelian-group-with-identity-e-prove-that-exists-an-ele%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












$begingroup$

If $G = bigoplus_{1 leq i leq k} mathbb{Z}_{n_i}$ with $n_i | n_{i+1}$, consider the element $(0,0, cdots ,1)$ with order $n_k$. It is clear that $exp G = n_k$.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Ah okay..Thanks!
    $endgroup$
    – Infinity
    Jan 7 at 4:52
















1












$begingroup$

If $G = bigoplus_{1 leq i leq k} mathbb{Z}_{n_i}$ with $n_i | n_{i+1}$, consider the element $(0,0, cdots ,1)$ with order $n_k$. It is clear that $exp G = n_k$.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Ah okay..Thanks!
    $endgroup$
    – Infinity
    Jan 7 at 4:52














1












1








1





$begingroup$

If $G = bigoplus_{1 leq i leq k} mathbb{Z}_{n_i}$ with $n_i | n_{i+1}$, consider the element $(0,0, cdots ,1)$ with order $n_k$. It is clear that $exp G = n_k$.






share|cite|improve this answer









$endgroup$



If $G = bigoplus_{1 leq i leq k} mathbb{Z}_{n_i}$ with $n_i | n_{i+1}$, consider the element $(0,0, cdots ,1)$ with order $n_k$. It is clear that $exp G = n_k$.







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered Jan 7 at 4:48









MathematicsStudent1122MathematicsStudent1122

8,62122467




8,62122467












  • $begingroup$
    Ah okay..Thanks!
    $endgroup$
    – Infinity
    Jan 7 at 4:52


















  • $begingroup$
    Ah okay..Thanks!
    $endgroup$
    – Infinity
    Jan 7 at 4:52
















$begingroup$
Ah okay..Thanks!
$endgroup$
– Infinity
Jan 7 at 4:52




$begingroup$
Ah okay..Thanks!
$endgroup$
– Infinity
Jan 7 at 4:52


















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%2f3064662%2flet-g-be-a-finite-abelian-group-with-identity-e-prove-that-exists-an-ele%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

android studio warns about leanback feature tag usage required on manifest while using Unity exported app?

SQL update select statement

'app-layout' is not a known element: how to share Component with different Modules