Contents
- Preface
7The Unit Circle: Sine and Cosine Functions
9Trigonometric Identities and Equations
- Introduction to Trigonometric Identities and Equations
- 9.1Verifying Trigonometric Identities and Using Trigonometric Identities to Simplify Trigonometric Expressions
- 9.2Sum and Difference Identities
- 9.3Double-Angle, Half-Angle, and Reduction Formulas
- 9.4Sum-to-Product and Product-to-Sum Formulas
- 9.5Solving Trigonometric Equations
11Systems of Equations and Inequalities
- AProofs, Identities, and Toolkit Functions
- Index
Chapter 12
Try It
12.1 Section Exercises
Show solution
1.An ellipse is the set of all points in the plane the sum of whose distances from two fixed points, called the foci, is a constant.
Show solution
37.Center Vertices Focus
Note that this ellipse is a circle. The circle has only one focus, which coincides with the center.
12.2 Section Exercises
Show solution
1.A hyperbola is the set of points in a plane the difference of whose distances from two fixed points (foci) is a positive constant.
12.3 Section Exercises
Show solution
1.A parabola is the set of points in the plane that lie equidistant from a fixed point, the focus, and a fixed line, the directrix.
12.4 Section Exercises
12.5 Section Exercises
Show solution
1.If eccentricity is less than 1, it is an ellipse. If eccentricity is equal to 1, it is a parabola. If eccentricity is greater than 1, it is a hyperbola.