1 00:00:01,045 --> 00:00:04,992 we are asked 'what number set does the number 8 belong to?' 2 00:00:04,992 --> 00:00:06,733 so this is actually a good review of the different 3 00:00:06,733 --> 00:00:09,311 sets of numbers we often talk about 4 00:00:09,311 --> 00:00:12,051 so the first set under consideration is 5 00:00:12,051 --> 00:00:13,733 the natural numbers 6 00:00:13,733 --> 00:00:17,067 natural numbers 7 00:00:17,067 --> 00:00:19,533 and these are essencially the counting numbers 8 00:00:19,533 --> 00:00:22,732 and you're not and not counting 0, 9 00:00:27,547 --> 00:00:30,714 1, 2, 3, so on and so forth 10 00:00:30,933 --> 00:00:32,879 so clearly 8 is a natural number, 11 00:00:32,879 --> 00:00:36,455 you can count up to 8 here, you can count 8 objects 12 00:00:36,455 --> 00:00:40,867 so 8 is a member of the natural numbers 13 00:00:40,867 --> 00:00:42,933 so it is a natural number, we should say 14 00:00:44,733 --> 00:00:46,164 the next one we should consider, 15 00:00:46,533 --> 00:00:49,180 let's consider the whole numbers 16 00:00:49,180 --> 00:00:54,474 whole numbers, right over here 17 00:00:54,474 --> 00:00:57,267 and i should say natural numbers 18 00:00:57,267 --> 00:00:58,839 so let's consider the whole numbers 19 00:00:58,839 --> 00:01:03,205 the whole numbers are essencially the same thing as the 20 00:01:03,205 --> 00:01:06,200 natural numbers, but we're now going to include the 0 21 00:01:06,200 --> 00:01:11,517 so it's 0, 1, 2, 3, so on and so forth 22 00:01:11,517 --> 00:01:13,793 so clearky 8 is one of these as well 23 00:01:13,793 --> 00:01:17,044 you could eventually increment your way to 8 like here 24 00:01:17,044 --> 00:01:18,669 just counting all of the whole numbers 25 00:01:18,669 --> 00:01:21,734 another way to view this is the non-negative numbers 26 00:01:21,734 --> 00:01:24,800 so 8 clearly belongs to this as well 27 00:01:24,800 --> 00:01:28,468 so let's expand our set a little bit, let's think about integers 28 00:01:28,468 --> 00:01:31,533 let's think about the set of integers 29 00:01:31,533 --> 00:01:34,800 now these are all the numbers starting with 30 00:01:34,800 --> 00:01:37,267 well, you could keep counting down, but all the way up to 31 00:01:37,267 --> 00:01:45,790 -3, -2, -1, 0, 1, 2, 3 and you could just keep going there 32 00:01:45,790 --> 00:01:48,200 now clearly 8 is one of these as well, you can just keep 33 00:01:48,200 --> 00:01:50,388 counting to 8, in fact, you can 34 00:01:50,388 --> 00:01:52,199 let me just put a check box there and 35 00:01:52,199 --> 00:01:55,775 in general, you have the integers that contain 36 00:01:55,775 --> 00:01:58,190 both the positive and the negative numbers 37 00:01:58,190 --> 99:59:59,999 and the 0