Trigonometry For Dummies, 3rd Edition

Chapter 15

Making Inverse Trig Work for You

IN THIS CHAPTER

Solving inverse functions

Dealing with multiple-angle inverse functions

Using identities to calculate inverses

In Chapter 14, I introduce you to the six inverse trig functions. As with many introductions to something new, it may take a while to place the name with the face (or in this case, properties). This chapter, on the other hand, takes you deeper into the world of inverses and shows how the inverses of trig functions work. You also see why you’d even want to bother learning the names with their good or bad traits.

Working with Inverses

One of the easiest ways to work with inverse trig functions is to have a chart handy with the exact values of the most frequently used functions, which you find in Tables 15-1 and 15-2 and in the Appendix. When angles other than the most common or popular ones are involved, you can resort to your handy-dandy calculator, the computer, or even your phone.

Now, on to making good use of the functions and their values. This first example on evaluating an inverse relation uses a value from the chart.

TABLE 15-1 Trig Values of the Most Commonly Used Functions

Degrees

Radians ...