Table of contents
- 0. Review of College Algebra4h 43m
- 1. Measuring Angles39m
- 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
5. Inverse Trigonometric Functions and Basic Trigonometric Equations
Inverse Sine, Cosine, & Tangent
Problem 6.7b
Textbook Question
Find the exact value of each real number y. Do not use a calculator.
y = tan⁻¹ (―√3)
![](/channels/images/assetPage/verifiedSolution.png)
1
Recognize that \( y = \tan^{-1}(\sqrt{3}) \) implies that \( \tan(y) = \sqrt{3} \).
Recall the special angles in trigonometry, specifically those in the unit circle, where the tangent function has known values.
Identify the angle \( y \) where \( \tan(y) = \sqrt{3} \). This occurs at \( y = \frac{\pi}{3} \) or \( y = 60^\circ \) in the first quadrant.
Consider the range of the inverse tangent function, which is \( (-\frac{\pi}{2}, \frac{\pi}{2}) \), to determine the principal value of \( y \).
Conclude that the exact value of \( y \) is \( \frac{\pi}{3} \) since it falls within the range of the inverse tangent function.
Recommended similar problem, with video answer:
![](/channels/images/assetPage/verifiedSolution.png)
This video solution was recommended by our tutors as helpful for the problem above
Video duration:
0m:0sPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Inverse Trigonometric Functions
Inverse trigonometric functions, such as tan⁻¹, are used to find angles when given a ratio of sides in a right triangle. For example, tan⁻¹(x) gives the angle whose tangent is x. Understanding how these functions work is crucial for solving problems involving angles and their corresponding trigonometric ratios.
Recommended video:
Introduction to Inverse Trig Functions
Tangent Function
The tangent function relates the angle of a right triangle to the ratio of the opposite side to the adjacent side. It is periodic and has a range of all real numbers. Knowing the values of the tangent function for common angles (like 30°, 45°, and 60°) helps in determining the angles corresponding to specific tangent values, such as -√3.
Recommended video:
Introduction to Tangent Graph
Quadrants and Angle Values
The unit circle is divided into four quadrants, each corresponding to different signs of the sine, cosine, and tangent functions. For instance, the tangent function is negative in the second and fourth quadrants. Understanding which quadrant an angle lies in is essential for determining the correct angle when solving for inverse trigonometric functions.
Recommended video:
Quadratic Formula
Watch next
Master Inverse Cosine with a bite sized video explanation from Callie Rethman
Start learningRelated Videos
Related Practice