meaning of a subgroup normalizes .
86872
normalized subgroup by another subgroup
49666
Generalization of index 2 subgroups are normal
58076
Subgroup generated by a set
129753
Prove that a subgroup which contains half of all elements is a normal subgroup.
51747
Showing that the intersection of all subgroups of order $n$ is normal
54911
The preimage of a normal subgroup under a group homomorphism is normal
113925
Normal Subgroup Counterexample
111375
Normality of subgroups and Sylow groups under homomorphisms...
75568
Subgroup of index $2$ is Normal
23941
Normal Subgroups that Intersect Trivially
57227
Maximal normal $\pi$-subgroups and torsion subgroups
74970
Subsubgroups are subgroups of subgroups / Multiplicative Property of the Index
141043
$H$ normal in $G$. Need $G$ contain a subgroup isomorphic to $G/H$
122266
equivalent definition of normal subgroup
120495
Does this correctly interpret the "$\cong$" between groups as "$=$" between sets?
36040
A Group Having a Cyclic Sylow 2-Subgroup Has a Normal Subgroup.
55350
H is a subgroup of G and G' is a subgroup of H. Prove H is normal in G.