Help with Set questions please

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The discussion focuses on solving set questions involving the set A = (-1, -2, 1, 2, 3, 5). For part i, participants are tasked with generating all possible fractions m/n where both m and n are elements from set A, resulting in a set of real numbers. In part ii, the goal is to identify which of these fractions simplify to integers, thus forming a subset of integers. Clarification was provided that the results of the fractions do not need to be in set A itself, only the combinations of m and n must come from A. Understanding the distinction between real numbers and integers in this context is crucial for solving the problems.
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Homework Statement



Hi, I need help with a couple of Set questions I just can't get my head around.

The question starts with:

Let

A = (-1, -2, 1, 2, 3, 5)

List the members of the following sets:

i) (x \in R: x = m/n for m, n \in A)

ii) (x \in Z: x = m/n for m, n \in A)


Homework Equations





The Attempt at a Solution



R will be real numbers and Z will be integers? I just can't seem to understand the rest. Any help ould be greatly appreciated.

Thanks
 
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Flook said:

Homework Statement



Hi, I need help with a couple of Set questions I just can't get my head around.

The question starts with:

Let

A = (-1, -2, 1, 2, 3, 5)

List the members of the following sets:

i) (x \in R: x = m/n for m, n \in A)

ii) (x \in Z: x = m/n for m, n \in A)

The Attempt at a Solution



R will be real numbers and Z will be integers? I just can't seem to understand the rest. Any help would be greatly appreciated.

Thanks

For i:

Generate all of the fractions you can make from the elements of set A, but using one element for the numerator and one element (possibly the same element) the denominator.

For ii:

Do the same as for part i, except you keep only the fractions which simplify to be integers.
 
Thanks for your response!

So for i)

I use A = (-1, -2, 1, 2, 3, 5) and make fractions, every possible combination?

-1/-2 = a half 1/2, but I wouldn't list that as it is not in set A?

so next would be -1/1 which is -1, so that is in set A?

I still don't get it I think.
 
No, the results don't have to be in A! You need to form all possible fractions- as the problem said, m/n with both m and n from A. All of those will be in (i) but only those that reduce to integers will be in (ii).
 
Ahh ok thank you HallsofIvy!
 

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