Calculate all the subgroups of D_4.(adsbygoogle = window.adsbygoogle || []).push({});

Which of them are normal subgroups? (It can

be shown that any subgroup containing half

the elements of a group G is a normal

subgroup, and if a has order 2 then {e,a} is

a normal subgroup iff a commutes with all

elements of G.)

{e,R^2} happens to be a normal subgroup.

Give the Cayley table of D_4/{e,R^2}.

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# Homework Help: Please help with Algebra problem

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