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Which negative infinity or positive infinity includes zero?
Brackets and a comma like that indicate a range, not just a list of 2 values
But those are parentheses, are they not? I was taught intervals using square brackets and semicolon. While parentheses are used for coordinates and tuples. The square brackets indicates inclusion of the boundary number.
Ie. the statement "2
Update: apparently either lemmy or my app (boost) wasn't that excited for my less than signs, and just skipped the rest of the comment. And here I had spent time copying both "less than or equal to" and infinity signs, since my keyboard doesn't seem to have them... For the time being pls disregard the comment above, while I figure out how to write math on lemmy.
It's likely just you were taught a different notation. Personally I was taught (x, y) can mean both coordinates x and y or a range from x-y (non inclusive), just depends on context which it is. Brackets like [x,y] I was taught are for inclusive ranges (i.e., x and y are included in the range)
So, what I was trying to do was use less than signs... Now I'll just write it out instead.
The nomenclature I was taught for intervals used square brackets. But both inclusive and exclusive. If the bracket opens toward the number it's inclusive, if the bracket opens away from the number it's excluded.
The example I tried to use was as follows, 2 less than x and x less than or equal to 5, would be written as x = ]2;5]. While 2 less than x, and x less than 5 would be x = ]2;5[, and 2 less than or equal to x, and x less than or equal to 5, would be x = [2;5]
But it is just nomenclature, but as any other kindergartener I always thought it was universal. Imagine my surprise when I discovered that some people uses a period for decimals and not a comma. And that English speakers uses the words millions, billions, and trillions but skips milliards, billiards, and trilliards. Meaning that translating between English and Daniah, you'd need to be keenly aware of the differences - otherwise you'd might try convincing a Dane that there are 1000x more people on earth.
Parentheses (also just called brackets here in North America, where the English language comes to die) are used to show that the listed values are not included in the range. They're always used for infinity since infinity isn't a real number.
So 0 to infinity would be [0, ∞). I think the semicolon vs comma is a regional style thing.
It's certainly between them somewhere
There is actually zero as well as negative zero for reasons beyond my comprehension
That was the root of what I was getting at, thanks lol.