I'm open and not closed
or closed but not open.
If I'm not, though I can be,
open and closed
or neither closed nor open.
Hint: math
Puzzling Stack Exchange is a question and answer site for those who create, solve, and study puzzles. It only takes a minute to sign up.
Sign up to join this communityI'm open and not closed
or closed but not open.
If I'm not, though I can be,
open and closed
or neither closed nor open.
Hint: math
Sets? Because they can be open, closed, both or neither open or closed?
Are you a(n)
interval?
I'm open and not closed
If an interval does not contain its endpoints it is open.
or closed but not open.
A closed interval does contain its endpoints.
If I'm not, though I can be,
open and closed
A half-open interval contains only one of its endpoints.
or neither closed nor open.
A degenerate interval only consists of one real number.
Hint:
An interval in math is a set of (real) numbers lying between the extremities.