Prove or disprove that the intersection of any collection
ofclosed sets is closed.

Intersection of collection of any closed set is a closed set.    

Step-by-step explanation:

Let F be a collection of arbitrary closed sets and let be closed set belonging to F.

We define a closed set as the set that contains its limit point or in other words it can be described that the complement or not of a closed set is an open set.

Thus, we can write R as

Now, applying De-Morgan's Theorem, we have

Since we knew are closed set, thus, is an open set.

We also know that union of all open set is an open set.

Thus, is an open set.

Thus, R is a closed set.

Hence, the theorem.  

4

step-by-step explanation:

im pretty sure it's 4 beacsue 8/2 equals 4