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# 1: Preliminaries

• • Contributed by David Arnold
• Retired Professor (Mathematics) at College of the Redwoods
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• 1.1: Number Systems
In this section we introduce the number systems that we will work with in the remainder of this text.
• 1.2: Solving Equations
In this section, we review the equation-solving skills that are prerequisite for successful completion of the material in this text. Before we list the tools used in the equation solving process, let’s make sure that we understand what is meant by the phrase “solve for x.”
• 1.3: Logic
Two of the most subtle words in the English language are the words “and” and “or.” One has only three letters, the other two, but it is absolutely amazing how much confusion these two tiny words can cause. Our intent in this section is to clear the mystery surrounding these words and prepare you for the mathematics that depends upon a thorough understanding of the words “and” and “or.”
• 1.4: Compound Inequalities
This section discusses a technique that is used to solve compound inequalities, which is a phrase that usually refers to a pair of inequalities connected either by the word “and” or the word “or.”
• 1.5: Chapter 1 Exercises with Solutions