ABSTRACT
This chapter discusses the facts about number systems. The natural numbers are convenient for counting and for labeling terms in sequences and elements in sets. The chapter explains the arithmetic operations of integers through the fundamental theorem of arithmetic. Although every integer has an additive inverse in the integers, most integers do not have a multiplicative inverse in the integers. The chapter presents an overview of operation of sets and reviews the basics concerning functions. Some exercise problems related to the concepts discussed in the chapter are also included.
