WEBVTT
00:00:00.680 --> 00:00:04.240
What is the set of π minus the set of π?
00:00:04.240 --> 00:00:10.240
The set π is a collection.
00:00:10.640 --> 00:00:15.560
Inside each of these sets is the same value.
00:00:16.280 --> 00:00:20.280
Imagine if the set of π contained five.
00:00:20.800 --> 00:00:27.360
Then what weβre saying is the set of five minus the set of five.
00:00:27.840 --> 00:00:30.480
And that would leave us with an empty set.
00:00:31.000 --> 00:00:33.400
There would be nothing in there.
00:00:33.880 --> 00:00:38.840
And the notation for an empty set or the null set looks like this.
00:00:39.440 --> 00:00:49.800
The set of π Minus the set of π equals the empty set, and we write the empty set with this symbol.