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I just started learning set theory.I have a question I need to answer for revision. I missed a bit of my lecture so i'm a little lost and I have yet to receive my textbook.

The question is: "Write [–3..1] as a set by explicitly listing all its elements. "

Just wondering how that works?

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    My gut reaction would be that this is impossible because $[-3,1]$ represents the set of all real numbers $x$ such that $-3\leq x\leq 1$. The fact that you are asked to do it, though, suggests to me that this is some special notation introduced in your course, possibly the set of all **integers** between $-3$ and $1$. If so, I would point out that I would "explicitly list" the set $[5..8]$ like so: $\{5,6,7,8\}$.2011-08-17
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    Thanks, I'll have to ask the professor. :)2011-08-17
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    @Arturo: $\{x\in\mathbb R\mid -3\le x\le 1\}$ is not explicit, I take it?2011-08-17
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    @Arturo Magidin: Note that the OP wrote $[-3..1]$, not $[-3,1]$.2011-08-18
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    @Asaf: It's not a way of "explicitly **listing** all the elements", no.2011-08-18
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    @Ben: Yes, which is what leads me to believe it's some sort of "local" notation; sorry I didn't make that clear in my comment (note I used the OPs notation in the last part).2011-08-18

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