Skip to main content
Ch. 1 - Trigonometric Functions
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 2, Problem 20

Use the appropriate reciprocal identity to find each function value. Rationalize denominators when applicable. See Example 1.
sin θ , given that csc θ = √24/3

Verified step by step guidance
1
Recall the reciprocal identity relating sine and cosecant: \(\sin \theta = \frac{1}{\csc \theta}\).
Substitute the given value of \(\csc \theta = \frac{\sqrt{24}}{3}\) into the identity: \(\sin \theta = \frac{1}{\frac{\sqrt{24}}{3}}\).
Simplify the complex fraction by multiplying numerator and denominator appropriately: \(\sin \theta = \frac{3}{\sqrt{24}}\).
Rationalize the denominator by multiplying numerator and denominator by \(\sqrt{24}\): \(\sin \theta = \frac{3 \times \sqrt{24}}{\sqrt{24} \times \sqrt{24}}\).
Simplify the denominator using the property \(\sqrt{a} \times \sqrt{a} = a\) and reduce the fraction if possible to express \(\sin \theta\) in simplest form.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
3m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Reciprocal Identities

Reciprocal identities relate trigonometric functions to their reciprocals, such as sin θ = 1/csc θ. These identities allow you to find one function value when its reciprocal is known, simplifying calculations and problem-solving.
Recommended video:
6:25
Pythagorean Identities

Rationalizing the Denominator

Rationalizing the denominator involves eliminating any radicals from the denominator of a fraction by multiplying numerator and denominator by a suitable expression. This process makes the expression simpler and more standard in form.
Recommended video:
2:58
Rationalizing Denominators

Simplifying Radicals

Simplifying radicals means expressing square roots in their simplest form by factoring out perfect squares. This helps in reducing expressions like √24 to 2√6, making calculations and rationalization easier.
Recommended video:
6:36
Simplifying Trig Expressions