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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

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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.

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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.
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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.
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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.
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