If n is an integer, n • 180° represents an integer multiple of 180°, (2n + 1) • 90° represents an odd integer multiple of 90° , and so on. Determine whether each expression is equal to 0, 1, or ―1, or is undefined. cos[n • 360°]
Table of contents
- 0. Review of College Algebra4h 45m
- 1. Measuring Angles40m
- 2. Trigonometric Functions on Right Triangles2h 5m
- 3. Unit Circle1h 19m
- 4. Graphing Trigonometric Functions1h 19m
- 5. Inverse Trigonometric Functions and Basic Trigonometric Equations1h 41m
- 6. Trigonometric Identities and More Equations2h 34m
- 7. Non-Right Triangles1h 38m
- 8. Vectors2h 25m
- 9. Polar Equations2h 5m
- 10. Parametric Equations1h 6m
- 11. Graphing Complex Numbers1h 7m
2. Trigonometric Functions on Right Triangles
Trigonometric Functions on Right Triangles
Problem 31
Textbook Question
Find the values of the six trigonometric functions for an angle in standard position having each given point on its terminal side. Rationalize denominators when applicable. (6√3 , ―6)
Verified step by step guidance1
Identify the coordinates of the point on the terminal side of the angle: \(x = 6\sqrt{3}\) and \(y = -6\).
Calculate the radius (or hypotenuse) \(r\) using the distance formula: \(r = \sqrt{x^2 + y^2} = \sqrt{(6\sqrt{3})^2 + (-6)^2}\).
Use the definitions of the six trigonometric functions in terms of \(x\), \(y\), and \(r\):
- \(\sin \theta = \frac{y}{r}\)
- \(\cos \theta = \frac{x}{r}\)
- \(\tan \theta = \frac{y}{x}\)
- \(\csc \theta = \frac{r}{y}\)
- \(\sec \theta = \frac{r}{x}\)
- \(\cot \theta = \frac{x}{y}\).
Substitute the values of \(x\), \(y\), and \(r\) into each function and simplify the expressions, rationalizing denominators where necessary.
Determine the signs of the trigonometric functions based on the quadrant in which the point lies (since \(x > 0\) and \(y < 0\), the point is in the fourth quadrant).
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Coordinates and the Terminal Side of an Angle
An angle in standard position has its vertex at the origin and its initial side along the positive x-axis. The given point (6√3, -6) lies on the terminal side of the angle, and its coordinates help determine the radius (distance from origin) and the signs of the trigonometric functions.
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Definition of the Six Trigonometric Functions Using Coordinates
The six trigonometric functions (sine, cosine, tangent, cosecant, secant, cotangent) can be defined using the coordinates (x, y) of a point on the terminal side and the radius r = √(x² + y²). Specifically, sin = y/r, cos = x/r, tan = y/x, and their reciprocals define the other three functions.
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Introduction to Trigonometric Functions
Rationalizing Denominators
When expressing trigonometric functions as fractions, denominators containing radicals should be rationalized for standard form. This involves multiplying numerator and denominator by a suitable radical to eliminate the root from the denominator, ensuring the expression is simplified and easier to interpret.
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Rationalizing Denominators
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