3 ms·

lol you didn't even describe what a 'closure' is ... just drew the equation. i stopped reading after that.

• dhaivatpandya 15y ago
  Um. I did. If you read on, I did explain what a closure was. If you don't get it, the concept is pretty simple, if you have two elements in a set S, and you apply the group operation on them, then the result must be in set S for the set in question to be a group.