- #1

snesnerd

- 26

- 0

## Homework Statement

If [itex](X,d)[/itex] is a metric space. I want to show that the set of all open balls and [itex]\emptyset[/itex] form a base.

## Homework Equations

## The Attempt at a Solution

I know that we need to show that the union of all these sets (or balls) is the whole set. I feel like this is simple yet, I am unsure what to write so that I do not miss any important facts.