Table of contents
- 0. Review of College Algebra(284)
- 1. Measuring Angles(327)
- 2. Trigonometric Functions on Right Triangles(205)
- 3. Unit Circle(231)
- 4. Graphing Trigonometric Functions(191)
- 5. Inverse Trigonometric Functions and Basic Trigonometric Equations(213)
- 6. Trigonometric Identities and More Equations(334)
- 7. Non-Right Triangles(117)
- 8. Vectors(160)
- 9. Polar Equations(82)
- 10. Parametric Equations(9)
- 11. Graphing Complex Numbers(91)
6. Trigonometric Identities and More Equations
Sum and Difference Identities
6. Trigonometric Identities and More Equations
Sum and Difference Identities: Study with Video Lessons, Practice Problems & Examples
112PRACTICE PROBLEM
Determine the exact value of the expression cos(x + y), given the following conditions:
tan x = -9/40, x in Quadrant II
cos y = 1/5, y in Quadrant I
Determine the exact value of the expression cos(x + y), given the following conditions:
tan x = -9/40, x in Quadrant II
cos y = 1/5, y in Quadrant I