Let k be an integer such that k divides n. Show that H = is a normal subgroup of Dn (Dihedral group). Then,...











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Let k be an integer such that k divides n. Show that H = is a normal subgroup of Dn (Dihedral group). Then, show that Dn/H is isomorphic to Dk.



I am totally lost here. I know in Dihedral group, r^n=e=s^2, srs=r^-1. However, I don't know how to proceed this question.






abstract-algebra







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  • Totally lost? Then first thing to do is to remind yourself of the definition of normal subgroup, and of $D_n/H$ (and second thing to do is to learn how to format mathematics on this website – check the Help menu).
    – Gerry Myerson
    11 hours ago















up vote
2
down vote

favorite












Let k be an integer such that k divides n. Show that H = is a normal subgroup of Dn (Dihedral group). Then, show that Dn/H is isomorphic to Dk.



I am totally lost here. I know in Dihedral group, r^n=e=s^2, srs=r^-1. However, I don't know how to proceed this question.






abstract-algebra







share|cite|improve this question






















  • Totally lost? Then first thing to do is to remind yourself of the definition of normal subgroup, and of $D_n/H$ (and second thing to do is to learn how to format mathematics on this website – check the Help menu).
    – Gerry Myerson
    11 hours ago













up vote
2
down vote

favorite









up vote
2
down vote

favorite











Let k be an integer such that k divides n. Show that H = is a normal subgroup of Dn (Dihedral group). Then, show that Dn/H is isomorphic to Dk.



I am totally lost here. I know in Dihedral group, r^n=e=s^2, srs=r^-1. However, I don't know how to proceed this question.






abstract-algebra







share|cite|improve this question













Let k be an integer such that k divides n. Show that H = is a normal subgroup of Dn (Dihedral group). Then, show that Dn/H is isomorphic to Dk.



I am totally lost here. I know in Dihedral group, r^n=e=s^2, srs=r^-1. However, I don't know how to proceed this question.






abstract-algebra




abstract-algebra






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked 11 hours ago









RandomThinker

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  • Totally lost? Then first thing to do is to remind yourself of the definition of normal subgroup, and of $D_n/H$ (and second thing to do is to learn how to format mathematics on this website – check the Help menu).
    – Gerry Myerson
    11 hours ago


















  • Totally lost? Then first thing to do is to remind yourself of the definition of normal subgroup, and of $D_n/H$ (and second thing to do is to learn how to format mathematics on this website – check the Help menu).
    – Gerry Myerson
    11 hours ago
















Totally lost? Then first thing to do is to remind yourself of the definition of normal subgroup, and of $D_n/H$ (and second thing to do is to learn how to format mathematics on this website – check the Help menu).
– Gerry Myerson
11 hours ago




Totally lost? Then first thing to do is to remind yourself of the definition of normal subgroup, and of $D_n/H$ (and second thing to do is to learn how to format mathematics on this website – check the Help menu).
– Gerry Myerson
11 hours ago















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