How many subgroups of order 4 does D_4 have?

nicekikah 2020-12-15 Answered
How many subgroups of order 4 does D4 have?
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Expert Answer

stuth1
Answered 2020-12-16 Author has 97 answers
We know that Dn is a dehedral group of order 2n. It is non-abelian group.
Therefore, the order of D4 is 8 and the list of elements is given by
D4={e,a,a2,a3,b,ba,ba2,ba3}
There are 3 subgroup of order in D4 which is given by
H1={e,a,a2,a3},
H2={e,b,a2,ba2}
H3={e,ba,a2,ba3}
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