Algebra factor group, Is solution correct?

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Homework Statement


G is a finite group. K is normal to G. If 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


(Kg)^n = K for some Kg in G/K.

(Kg)^n = (Kg^n) = K, hence g^n = 1 where g is an element of G.

Is this all there was to it? Did I skip a step going from (Kg)^n --> (Kg^n)
 
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Not correct. Very sloppy. Kg^n=K doesn't tell you g^n=1. It tells you g^n is an element of K.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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