Infinite Order of Non-Identity Elements

In summary, in an abelian group G with a subgroup H of elements of finite order, it can be proven that every non-identity element in G/H has infinite order. This is done by showing that if gH has order n, then g must be the identity element, which leads to a contradiction. Therefore, the statement holds true.
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Homework Statement


G is an abelian group with H the subgroup of elements of G with finite order. Prove that every non-identity element in G/H has infinite order.

Homework Equations


The Attempt at a Solution


Suppose gH in G/H has order n.
Then (gH)n = gnH so gn is in H.
Then there is some m > 0 such that gnm = e.
So g is in H.

At this point, I am stuck - I do not know how to show that g must be the identity element.

EDIT: Figured it out.
 
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Since g is in H, then g has a finite order m. Since (gH)n = eH = H, then m must divide n.But this is a contradiction since the order of gH is n. Therefore g must be the identity element and the statement is proven.
 

What is the Infinite Order of Non-Identity Elements?

The Infinite Order of Non-Identity Elements refers to a concept in abstract algebra that describes the order, or size, of a group of elements that are not equal to the identity element. This order can be infinite, meaning that there is no limit to the number of times an element can be combined with itself to result in the identity element.

How do you determine the Infinite Order of Non-Identity Elements?

The Infinite Order of Non-Identity Elements can be determined by finding the smallest positive integer n such that the element multiplied by itself n times results in the identity element. If no such n exists, the element has an infinite order.

Can the Infinite Order of Non-Identity Elements be negative?

No, the Infinite Order of Non-Identity Elements cannot be negative. The order of a group is defined as a positive integer or infinity, so it cannot have a negative value.

What is an example of an element with an Infinite Order of Non-Identity Elements?

An example of an element with an Infinite Order of Non-Identity Elements is the set of all integers under addition. No matter how many times an integer is added to itself, it will never result in the identity element (zero), making its order infinite.

How does the Infinite Order of Non-Identity Elements relate to the concept of a group?

In abstract algebra, a group is a set of elements with a defined operation that satisfies certain properties. The Infinite Order of Non-Identity Elements is a characteristic of a group that describes the size and behavior of its non-identity elements.

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