MATH 3333
Solutions: Homework Assignment #4
1. Determine whether the given set is open, closed, or neither open nor closed.(a)S= (-1,2)∪[3,∞) Neither
(b)S= (-∞,1)∪(2,∞) Open: every point of
(d)S=braceleftbigg0,12,23,34,· · ·,n-1n,· · ·bracerightbigg∪[1,4]
