SUMMARY
The exact value of \( y = \cos\left(\arcsin\frac{5}{11}\right) \) can be determined using the Pythagorean identity \( 1 = \cos^2(\theta) + \sin^2(\theta) \). Given that \( \sin(\theta) = \frac{5}{11} \), we find \( \cos(\theta) \) by rearranging the identity to \( \cos^2(\theta) = 1 - \left(\frac{5}{11}\right)^2 \). This leads to \( \cos(\theta) = \sqrt{1 - \frac{25}{121}} = \sqrt{\frac{96}{121}} = \frac{4\sqrt{6}}{11} \). The discussion emphasizes the importance of recognizing that \( \theta = \arcsin\frac{5}{11} \) is restricted to the first quadrant, where cosine is positive.
PREREQUISITES
- Understanding of inverse trigonometric functions, specifically arcsin
- Familiarity with the Pythagorean identity in trigonometry
- Basic knowledge of right triangle properties
- Ability to manipulate algebraic expressions involving square roots
NEXT STEPS
- Study the properties of inverse trigonometric functions and their ranges
- Learn how to apply the Pythagorean identity in various trigonometric contexts
- Explore the unit circle and its relation to sine and cosine values
- Practice solving similar problems involving \( \sin \) and \( \cos \) with different values
USEFUL FOR
Students studying trigonometry, educators teaching inverse functions, and anyone looking to deepen their understanding of trigonometric identities and their applications.