(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

They seem to be pretty similar. It seems like you could switch the two around and things would still make sense.

Although a ball is a set, and a neighborhood is a region, I guess? So is the set of all y in a neighborhood of x the ball?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: What's the difference between a ball and a neighborhood?

**Physics Forums | Science Articles, Homework Help, Discussion**