If G solvable and S a subgroup, then S is solvable [duplicate]












0















This question already has an answer here:




  • Subgroups of finite solvable groups. Solvable?

    2 answers




Let $G$ be a solvable group, and $S$ a subgroup. Prove that $S$ is solvable.



Let $G$ be solvable. Then there exists a sequence of subgroups $$ { e}triangleleft H_rtriangleleft H_{r-1}cdots triangleleft H_1 triangleleft H_0=G $$ such that $H_{i+1}triangleleft H_i$ for $i=0, ...r-1,$ and $H_i/H_{i+1}$ is abelian. If $S=H_i$, where $H_i$ is as above for $ineq r$, then it is trivial. So we need to assume that $Sneq H_i.$ Let $N_S$ be the normalizer of $S$ in $G$. We know that $Striangleleft N_S$ and $N_S$ is a subgroup of $G.$ Here I am stuck.



Can somebody propose a solution or give me some hint. Thanks.










share|cite|improve this question















marked as duplicate by Jyrki Lahtonen abstract-algebra
Users with the  abstract-algebra badge can single-handedly close abstract-algebra questions as duplicates and reopen them as needed.

StackExchange.ready(function() {
if (StackExchange.options.isMobile) return;

$('.dupe-hammer-message-hover:not(.hover-bound)').each(function() {
var $hover = $(this).addClass('hover-bound'),
$msg = $hover.siblings('.dupe-hammer-message');

$hover.hover(
function() {
$hover.showInfoMessage('', {
messageElement: $msg.clone().show(),
transient: false,
position: { my: 'bottom left', at: 'top center', offsetTop: -7 },
dismissable: false,
relativeToBody: true
});
},
function() {
StackExchange.helpers.removeMessages();
}
);
});
});
Dec 27 '18 at 17:30


This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.




















    0















    This question already has an answer here:




    • Subgroups of finite solvable groups. Solvable?

      2 answers




    Let $G$ be a solvable group, and $S$ a subgroup. Prove that $S$ is solvable.



    Let $G$ be solvable. Then there exists a sequence of subgroups $$ { e}triangleleft H_rtriangleleft H_{r-1}cdots triangleleft H_1 triangleleft H_0=G $$ such that $H_{i+1}triangleleft H_i$ for $i=0, ...r-1,$ and $H_i/H_{i+1}$ is abelian. If $S=H_i$, where $H_i$ is as above for $ineq r$, then it is trivial. So we need to assume that $Sneq H_i.$ Let $N_S$ be the normalizer of $S$ in $G$. We know that $Striangleleft N_S$ and $N_S$ is a subgroup of $G.$ Here I am stuck.



    Can somebody propose a solution or give me some hint. Thanks.










    share|cite|improve this question















    marked as duplicate by Jyrki Lahtonen abstract-algebra
    Users with the  abstract-algebra badge can single-handedly close abstract-algebra questions as duplicates and reopen them as needed.

    StackExchange.ready(function() {
    if (StackExchange.options.isMobile) return;

    $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() {
    var $hover = $(this).addClass('hover-bound'),
    $msg = $hover.siblings('.dupe-hammer-message');

    $hover.hover(
    function() {
    $hover.showInfoMessage('', {
    messageElement: $msg.clone().show(),
    transient: false,
    position: { my: 'bottom left', at: 'top center', offsetTop: -7 },
    dismissable: false,
    relativeToBody: true
    });
    },
    function() {
    StackExchange.helpers.removeMessages();
    }
    );
    });
    });
    Dec 27 '18 at 17:30


    This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.


















      0












      0








      0








      This question already has an answer here:




      • Subgroups of finite solvable groups. Solvable?

        2 answers




      Let $G$ be a solvable group, and $S$ a subgroup. Prove that $S$ is solvable.



      Let $G$ be solvable. Then there exists a sequence of subgroups $$ { e}triangleleft H_rtriangleleft H_{r-1}cdots triangleleft H_1 triangleleft H_0=G $$ such that $H_{i+1}triangleleft H_i$ for $i=0, ...r-1,$ and $H_i/H_{i+1}$ is abelian. If $S=H_i$, where $H_i$ is as above for $ineq r$, then it is trivial. So we need to assume that $Sneq H_i.$ Let $N_S$ be the normalizer of $S$ in $G$. We know that $Striangleleft N_S$ and $N_S$ is a subgroup of $G.$ Here I am stuck.



      Can somebody propose a solution or give me some hint. Thanks.










      share|cite|improve this question
















      This question already has an answer here:




      • Subgroups of finite solvable groups. Solvable?

        2 answers




      Let $G$ be a solvable group, and $S$ a subgroup. Prove that $S$ is solvable.



      Let $G$ be solvable. Then there exists a sequence of subgroups $$ { e}triangleleft H_rtriangleleft H_{r-1}cdots triangleleft H_1 triangleleft H_0=G $$ such that $H_{i+1}triangleleft H_i$ for $i=0, ...r-1,$ and $H_i/H_{i+1}$ is abelian. If $S=H_i$, where $H_i$ is as above for $ineq r$, then it is trivial. So we need to assume that $Sneq H_i.$ Let $N_S$ be the normalizer of $S$ in $G$. We know that $Striangleleft N_S$ and $N_S$ is a subgroup of $G.$ Here I am stuck.



      Can somebody propose a solution or give me some hint. Thanks.





      This question already has an answer here:




      • Subgroups of finite solvable groups. Solvable?

        2 answers








      abstract-algebra group-theory






      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 17:28

























      asked Dec 27 '18 at 17:22









      user249018

      393127




      393127




      marked as duplicate by Jyrki Lahtonen abstract-algebra
      Users with the  abstract-algebra badge can single-handedly close abstract-algebra questions as duplicates and reopen them as needed.

      StackExchange.ready(function() {
      if (StackExchange.options.isMobile) return;

      $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() {
      var $hover = $(this).addClass('hover-bound'),
      $msg = $hover.siblings('.dupe-hammer-message');

      $hover.hover(
      function() {
      $hover.showInfoMessage('', {
      messageElement: $msg.clone().show(),
      transient: false,
      position: { my: 'bottom left', at: 'top center', offsetTop: -7 },
      dismissable: false,
      relativeToBody: true
      });
      },
      function() {
      StackExchange.helpers.removeMessages();
      }
      );
      });
      });
      Dec 27 '18 at 17:30


      This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.






      marked as duplicate by Jyrki Lahtonen abstract-algebra
      Users with the  abstract-algebra badge can single-handedly close abstract-algebra questions as duplicates and reopen them as needed.

      StackExchange.ready(function() {
      if (StackExchange.options.isMobile) return;

      $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() {
      var $hover = $(this).addClass('hover-bound'),
      $msg = $hover.siblings('.dupe-hammer-message');

      $hover.hover(
      function() {
      $hover.showInfoMessage('', {
      messageElement: $msg.clone().show(),
      transient: false,
      position: { my: 'bottom left', at: 'top center', offsetTop: -7 },
      dismissable: false,
      relativeToBody: true
      });
      },
      function() {
      StackExchange.helpers.removeMessages();
      }
      );
      });
      });
      Dec 27 '18 at 17:30


      This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
























          1 Answer
          1






          active

          oldest

          votes


















          1














          suppose that $G$ is resolvable and that ${H_i}_0^n$ is a series of composition of $G$ such that $H_{i+1}/H_i$ is cyclic $0leq ileq n-1$. Let $T$ be a subgroup $G$ either. For each $i$ we can define $T_i=Tcap H_i$ so that $T_i$ is a subgroup of $T$. Avoiding the duplication of those $T_i$ that are repeated, that is, those that comply with $Tcap H_i=Tcap H_{i+1}$ we can form a series of $T$ composition.
          $${e}=T_0’leq cdots T_m’=T$$
          Then $T_{i+1}’/T_i’=(Tcap H_{i+1})/(Tcap H_i)$ is a cyclic group. Therefore $T$ es resolvable.






          share|cite|improve this answer




























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            1














            suppose that $G$ is resolvable and that ${H_i}_0^n$ is a series of composition of $G$ such that $H_{i+1}/H_i$ is cyclic $0leq ileq n-1$. Let $T$ be a subgroup $G$ either. For each $i$ we can define $T_i=Tcap H_i$ so that $T_i$ is a subgroup of $T$. Avoiding the duplication of those $T_i$ that are repeated, that is, those that comply with $Tcap H_i=Tcap H_{i+1}$ we can form a series of $T$ composition.
            $${e}=T_0’leq cdots T_m’=T$$
            Then $T_{i+1}’/T_i’=(Tcap H_{i+1})/(Tcap H_i)$ is a cyclic group. Therefore $T$ es resolvable.






            share|cite|improve this answer


























              1














              suppose that $G$ is resolvable and that ${H_i}_0^n$ is a series of composition of $G$ such that $H_{i+1}/H_i$ is cyclic $0leq ileq n-1$. Let $T$ be a subgroup $G$ either. For each $i$ we can define $T_i=Tcap H_i$ so that $T_i$ is a subgroup of $T$. Avoiding the duplication of those $T_i$ that are repeated, that is, those that comply with $Tcap H_i=Tcap H_{i+1}$ we can form a series of $T$ composition.
              $${e}=T_0’leq cdots T_m’=T$$
              Then $T_{i+1}’/T_i’=(Tcap H_{i+1})/(Tcap H_i)$ is a cyclic group. Therefore $T$ es resolvable.






              share|cite|improve this answer
























                1












                1








                1






                suppose that $G$ is resolvable and that ${H_i}_0^n$ is a series of composition of $G$ such that $H_{i+1}/H_i$ is cyclic $0leq ileq n-1$. Let $T$ be a subgroup $G$ either. For each $i$ we can define $T_i=Tcap H_i$ so that $T_i$ is a subgroup of $T$. Avoiding the duplication of those $T_i$ that are repeated, that is, those that comply with $Tcap H_i=Tcap H_{i+1}$ we can form a series of $T$ composition.
                $${e}=T_0’leq cdots T_m’=T$$
                Then $T_{i+1}’/T_i’=(Tcap H_{i+1})/(Tcap H_i)$ is a cyclic group. Therefore $T$ es resolvable.






                share|cite|improve this answer












                suppose that $G$ is resolvable and that ${H_i}_0^n$ is a series of composition of $G$ such that $H_{i+1}/H_i$ is cyclic $0leq ileq n-1$. Let $T$ be a subgroup $G$ either. For each $i$ we can define $T_i=Tcap H_i$ so that $T_i$ is a subgroup of $T$. Avoiding the duplication of those $T_i$ that are repeated, that is, those that comply with $Tcap H_i=Tcap H_{i+1}$ we can form a series of $T$ composition.
                $${e}=T_0’leq cdots T_m’=T$$
                Then $T_{i+1}’/T_i’=(Tcap H_{i+1})/(Tcap H_i)$ is a cyclic group. Therefore $T$ es resolvable.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Dec 27 '18 at 17:47









                Julio Trujillo Gonzalez

                856




                856















                    Popular posts from this blog

                    Human spaceflight

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

                    File:DeusFollowingSea.jpg