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Ch. 5 - Trigonometric Identities
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 6, Problem 12

Perform each indicated operation and simplify the result so that there are no quotients.
sec x/csc x + csc x/sec x

Verified step by step guidance
1
Recall the definitions of the secant and cosecant functions in terms of sine and cosine: \(\sec x = \frac{1}{\cos x}\) and \(\csc x = \frac{1}{\sin x}\).
Rewrite each quotient in the expression \(\frac{\sec x}{\csc x} + \frac{\csc x}{\sec x}\) by substituting the definitions: \(\frac{\frac{1}{\cos x}}{\frac{1}{\sin x}} + \frac{\frac{1}{\sin x}}{\frac{1}{\cos x}}\).
Simplify each complex fraction by multiplying numerator and denominator appropriately: \(\frac{1}{\cos x} \times \frac{\sin x}{1} + \frac{1}{\sin x} \times \frac{\cos x}{1}\).
This simplifies to \(\frac{\sin x}{\cos x} + \frac{\cos x}{\sin x}\), which are simpler trigonometric expressions without quotients of sec and csc.
To combine and simplify further, find a common denominator \(\sin x \cos x\) and write the expression as \(\frac{\sin^2 x}{\sin x \cos x} + \frac{\cos^2 x}{\sin x \cos x}\), then combine the numerators.

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Key Concepts

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

Reciprocal Trigonometric Functions

Secant (sec x) and cosecant (csc x) are reciprocal functions of cosine and sine, respectively. Specifically, sec x = 1/cos x and csc x = 1/sin x. Understanding these relationships helps in rewriting expressions to simplify or eliminate quotients.
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Simplifying Complex Fractions

Complex fractions involve fractions within fractions. To simplify, rewrite all terms with common denominators or multiply numerator and denominator by the least common denominator to eliminate nested fractions, making the expression easier to handle.
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Trigonometric Identities and Simplification

Using fundamental identities like sin²x + cos²x = 1 allows for rewriting and simplifying expressions. Recognizing opportunities to combine terms or convert to sine and cosine helps reduce the expression to a simpler form without quotients.
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