bd40bc7c7a These two interpretations of slope help prepare students for the concept of the derivative in calculus. If you are providing a link to students or a bookstore to purchase printed copies of the book, please direct them to this page. CHAPTER 5 Trigonometric Functions: Unit Circle Approach This chapter includes a new subsection on the concept of phase shift as used in modeling harmonic motion. Section 3.6, Rational Functions, has a new subsection on rational functions with holes. Solutions updated: April 20, 2015.