
Facebook Page // Twitter Page
15 Comments
Leave a comment
Profile pictures are tied to your email address and can
be set up at Gravatar.
Click here for recent comments.
(Note: You must have javascript enabled to leave comments, otherwise you will get a comment submission error.)
If you make a mistake or the comment doesn't show up properly, email me and I'll gladly fix it :-).
(Note: You must have javascript enabled to leave comments, otherwise you will get a comment submission error.)
If you make a mistake or the comment doesn't show up properly, email me and I'll gladly fix it :-).
Facebook Page // Twitter Page
New to Spiked Math?
View the top comics.
New Feature: Browse the archives in quick view! Choose from a black, white or grey background.
View the top comics.
New Feature: Browse the archives in quick view! Choose from a black, white or grey background.
by Pablo and Leonardo
(Ranked by SM-CRA)
Spiked Math Forum (beta)
Math Games (beta)






I know I should get this, I've seen it in class before...
Nice! Empty set store is both open and closed!
Maybe they should put it in a box, and then open the box?
Maybe it's Schrödinger's cafe and they won't know whether it's open or closed until they try to open the doors.
Don't go in...
probably no food in there anyways ^_^
originally i wanted (711) to be in the middle... the store 7-11 is indeed open 24/7, but viewing it as a set with one element doesn't quite fit the joke :-(
couldn't you have put (7, 11) then? instead of (711)?
It doesn't matter if it's open or closed: once you get it, it's no longer the null set!
Unless there is no floor...
Just thought you'd like to know, I showed this to my math teacher and she got a kick out of it. Good stuff.
Nupanick now get extra credit for showing her this...
yes, but once they enter, is it a closed or open set?
Don't you know? It's called "clopen"!
Also, my Topolgy Professor tells me that "clopen" is a four-letter word, lol.
My professor has a sign outside his office, "Clopen' and I always have to pause before I knock on the door. Drives me insane. What sick mathematician decided it was cool to let sets be open and close at the same time?