When you don't know, if you don't know, or don't remember any concept.
Random person 1: Dude, there's this math question I recently saw on the Internet, do you know how it works? *shows problem*
Random person 2: I don't knowmember that formula, it's been a while since I've studied complex math equations.
Random person 2: I don't knowmember that formula, it's been a while since I've studied complex math equations.
by PCubiles June 16, 2021