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is it just me? does this inequality question make sense?

In this course I am studying. I am presented with a question, here...

Untitled.png

i don't know how well that can be read....

it basically says: In set notation, we can write this x<=-3 and x>=-2 as....

So, and usually refers to symbol n.. and in this case saying {x: 3<= x <= -2} cannot exist.... so it can only be {x:x<=-3}u{x:x>=-2} but then sholdn't the question say: In set notation, we can write this x<=-3 or x>=-2 as..

or am i just thinking too much into this?
(edited 11 months ago)
Reply 1
Original post by KingRich
In this course I am studying. I am presented with a question, here...

Untitled.png

i don't know how well that can be read....

it basically says: In set notation, we can write this x<=-3 and x>=-2 as....

So, and usually refers to symbol n.. and in this case saying {x: 3<= x <= -2} cannot exist.... so it can only be {x:x<=-3}u{x:x>=-2} but then sholdn't the question say: In set notation, we can write this x<=-3 or x>=-2 as..
or am i just thinking too much into this?

What is the next line(s). You can have an empty set, so it would be possible to find the intersection "n" of the two stated inequalities.
Reply 2
Original post by mqb2766
What is the next line(s). You can have an empty set, so it would be possible to find the intersection "n" of the two stated inequalities.

Sorry, I hadn’t received a notification saying anyone responded.

There’s no second line. That’s everything provided in regards to the question.

That’s why I’m a little baffled by it lol

It seems an incomplete question to me.
Reply 3
Original post by KingRich
Sorry, I hadn’t received a notification saying anyone responded.

There’s no second line. That’s everything provided in regards to the question.

That’s why I’m a little baffled by it lol

It seems an incomplete question to me.


It could be that it refers to the intersection and the result is an empty set, it could be that and is used as normal so theyre two unrelated inequalities, it could be typo, .... take your pick if there is no further info.
Reply 4
Original post by mqb2766
It could be that it refers to the intersection and the result is an empty set, it could be that and is used as normal so theyre two unrelated inequalities, it could be typo, .... take your pick if there is no further info.


Well, I went ahead and chose n and brought their attention to the question about it seeming Incomplete or perhaps a typo and they said it’s impossible to be both sets, so it had to be U.

however, as you just mentioned. Empty sets can exists. So, I was right to think that it did seem a bit incomplete.
Reply 5
Original post by KingRich
Well, I went ahead and chose n and brought their attention to the question about it seeming Incomplete or perhaps a typo and they said it’s impossible to be both sets, so it had to be U.

however, as you just mentioned. Empty sets can exists. So, I was right to think that it did seem a bit incomplete.

The actual result is fairly irrelevant as they simply want you to use the set notation so u or n, irrespective of any understanding of the result. Sounds like a typo, Id not pay too much attention to it.

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