Does a Factor Group Element's Order Imply the Same Order in the Original Group?

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SUMMARY

In the discussion, participants analyze the relationship between the order of an element in a factor group G/K and the original group G. It is established that if Kg is an element in G/K with order n, then (Kg)^n = K implies that g^n is in the normal subgroup K. However, this does not guarantee that g has order n in G, as it only indicates that g^n is an element of K. The conclusion is that the order of an element in the factor group does not necessarily imply the same order in the original group.

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Homework Statement


Let G be a finite group and let K be normal to G. If the factor group G/K has an element of order n, show that G has an element of order n.

Homework Equations


None

The Attempt at a Solution


Lets say Kg is the element in G/K with order n.
That means:
(Kg)^n = K

and from properties of factor groups we know:
(Kg)^n = Kg^n
so Kg^n = K
hence g^n = 1
if g^n = 1 then it must be in G, because G has the identity (1).

Is this correct thinking?
 
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PsychonautQQ said:

Homework Statement


Let G be a finite group and let K be normal to G. If the factor group G/K has an element of order n, show that G has an element of order n.

Homework Equations


None

The Attempt at a Solution


Lets say Kg is the element in G/K with order n.
That means:
(Kg)^n = K

and from properties of factor groups we know:
(Kg)^n = Kg^n
so Kg^n = K
hence g^n = 1
if g^n = 1 then it must be in G, because G has the identity (1).

Is this correct thinking?

No. Haven't you posted this before? Kg^n=K only tells you that g^n is in K.
 

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