1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Help 'set' question

  1. Oct 6, 2008 #1
    help!!!!! 'set' question

    Give an example in the set notation of a CLOSED set S in R^2 such that the closure of int S is not equal to S.

    I originally used the set

    s={ (x,y) : 0 <x^2+y^2<1}
    but I just noticed it's not closed set!
    ...

    can anyone give me an example?

    Thanks!
     
  2. jcsd
  3. Oct 6, 2008 #2

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    Re: help!!!!! 'set' question

    No, but I can suggest something to try: if S is a finite set of points, what is its interior? What is the closure of that?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Help 'set' question
  1. Question on sets (Replies: 12)

Loading...