"Let I be the set of real numbers that are greater than 0. For each x I, let be the open interval (0,x). Prove that = , = I. For each x I, let be the closed interval [o, x]. Prove that = {0}, = I {0}."
"Let I be the set of real numbers that are greater than 0. For each x I, let be the open interval (0,x). Prove that = , = I. For each x I, let be the closed interval [o, x]. Prove that = {0}, = I {0}."