Homework for Math 362A
Spring, 2008


Problem Set

Chapter

Problems

01 [NA] Look over the course webpage. In particular, read through the course syllabus, get accustomed to requesting a course calendar, and look over the interface for getting homework assignments.
∗1 Prove the assertion: If (X, d ) is a metric space and Y is a subset of X, then (Y, d ) is a metric space.
∗2 Prove the assertion: If (xn ) is a Cauchy sequence in a metric space (X, d ), then the set {xn | n = 1, 2, ...} is bounded.
∗3 Prove the assertion: Suppose (X, d ) is a complete metric space, and (xn ) is a sequence in X. Then (xn ) is convergent if and only if it is Cauchy.
Note: An “if and only if” statement always makes two assertions. Which, if either one, of the two assertions made here still holds if X is not complete?
2 11

Notation

n manditory problem
∗n manditory problem, not from text
(n) helper problem
[n] ungraded problem
{n} optional problem