Are the Sets {r, -r, 0} and {-r, r, 0} Identical?

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The sets {r, -r, 0} and {-r, r, 0} are identical because, in set theory, the order of elements does not matter. Both sets contain the same elements, making them equal. It is important to use curly brackets to denote sets, as other types of brackets imply different mathematical objects where order is significant. The discussion emphasizes that two collections are considered the same if they contain the same elements, regardless of order. Therefore, the answer is yes, the sets are the same.
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Homework Statement


Is the set (r,-r,0) the same as the set (-r,r,0)

Sorry I need to know the answer to this right now, somebody in class confused me and I can't talk to my teacher right now.

My answer: yes it is the same set. Can anyone just give me a quick yes/no?

Homework Equations

The Attempt at a Solution

 
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I have to brake for a car in front of me, so I can't answer 'it depends' right now ! :rolleyes:

good luck with your test !
 
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Rijad Hadzic said:

Homework Statement


Is the set (r,-r,0) the same as the set (-r,r,0)

Sorry I need to know the answer to this right now, somebody in class confused me and I can't talk to my teacher right now.

My answer: yes it is the same set. Can anyone just give me a quick yes/no?

Homework Equations

The Attempt at a Solution

Yes, as sets they are the same. Order doesn't matter here.
 
I wasn't really in a car, but safely behind my desktop. Just didn't want to interfere in a testing situation :rolleyes:

If the order of elements in a set matters, we call it a sequence. (You need a sequence of instructions when asking directions; with a set you wouldn't know what to do first)

A set is a collection. Two collections are the same if they contain the same elements. Yours do
 
Rijad Hadzic said:

Homework Statement


Is the set (r,-r,0) the same as the set (-r,r,0)

Sorry I need to know the answer to this right now, somebody in class confused me and I can't talk to my teacher right now.

My answer: yes it is the same set. Can anyone just give me a quick yes/no?

Homework Equations

The Attempt at a Solution


Your notation is poor: in Mathematics, we almost always denote sets using curly brackets, like this: ##\{ r, -r,0 \}##, and in that case, order does not matter: ##\{ r,-r,0 \} = \{ r,-r,0 \} = \{ r,0,-r \} = \{ -r,0,r \} = \{ 0,r,-r \} = \{ 0,-r,r \}. ## Other types of brackets like ( , ) , [ , ] or < , > denote objects like lists, vectors, arrays, sequences, etc., and for all of them order is crucial.
 
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