00:01
Hi, in this question we have to show that the finite union of a compact state is compact.
00:07
We will first say that let a1, a2 till an.
00:12
This be the compact sets.
00:20
We consider an open cover that is a1 union, a2 union, so on till an.
00:31
This open cover must cover a.
00:34
So ai individually and because ai is compact, there must be a finite subcover for ai.
00:48
So then we can say that the union of this n subcover, it is finite and clearly it covers even till a .n.
01:12
Therefore every open cover that is a1 union till a .n has a finite subcover and therefore we can say even union till a .n is compact.
01:42
Hence we have proved.
01:44
Further we can say that we have to give an example that an infinite union of an infight union of an infight.
01:55
Finite compact set it is not compact...