00:01
Which of these collections of sets are partitioned the set as which is one, two, three, four, five, six? so the definition of partition means that if you have a collection of sets, then you take a union of all these sets and then you put us the main of the practitioners.
00:26
The thing about the case is sometimes things like this, if not the union of these two sets here is not 1, 2, 3, 4, but instead 1, 2, 2, 3, 4.
00:40
Sets can have repetitions unlike, yeah.
00:53
No, sorry, sets cannot have repetitions unlike lists.
00:58
So here, if you take the union of all of these sets, you get 1, 2, 2, 3, 4, 4, 5, 6, so they're not this joint, so therefore they don't partition the set s.
01:17
Here, this set here and this set here are not this joint because they share are two, and these two share are four.
01:25
Now for the other set, in part b we're given the set the collection 1.
01:38
And to make this simpler, instead of writing the curly braces for sets, i'm just going to write, i'm just going to list out elements in the set.
01:46
Here we're given 1, and we're given 2, 3, 6, and we're given 4 and 5.
02:03
Well, if we take the union in all of these sets, we do, in fact, if we take the unit of 1, 2, 3, 6, and 4, if we get 1, 2, 3, 6, and 1, 2, 6, the unit of 4, and the unit of 5, which is just 4, 5...