In Exercises 63β84, use an identity to solve each equation on the interval [0, 2π ). sin x + cos x = 1
Ch. 3 - Trigonometric Identities and Equations

Chapter 3, Problem 83
In Exercises 63β84, use an identity to solve each equation on the interval [0, 2π ). tan x + sec x = 1
Verified step by step guidance1
Start with the given equation: \(\tan x + \sec x = 1\).
Recall the definitions of tangent and secant in terms of sine and cosine: \(\tan x = \frac{\sin x}{\cos x}\) and \(\sec x = \frac{1}{\cos x}\).
Rewrite the equation using these definitions: \(\frac{\sin x}{\cos x} + \frac{1}{\cos x} = 1\).
Combine the terms on the left-hand side over a common denominator: \(\frac{\sin x + 1}{\cos x} = 1\).
Multiply both sides of the equation by \(\cos x\) (noting \(\cos x \neq 0\)) to get: \(\sin x + 1 = \cos x\). Then, rearrange to isolate terms and use Pythagorean identities to solve for \(x\) in the interval \([0, 2\pi)\).

Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
6mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Trigonometric Identities
Trigonometric identities are equations involving trigonometric functions that hold true for all values within their domains. In this problem, identities like sec x = 1/cos x and tan x = sin x/cos x help transform the equation into a solvable form by expressing all terms in sine and cosine.
Recommended video:
Fundamental Trigonometric Identities
Solving Trigonometric Equations
Solving trigonometric equations involves manipulating the equation using identities and algebraic techniques to isolate the variable. After simplification, solutions are found by determining the angles that satisfy the equation within the given interval [0, 2Ο).
Recommended video:
How to Solve Linear Trigonometric Equations
Domain and Interval Considerations
When solving trigonometric equations, it is essential to consider the specified interval, here [0, 2Ο), to find all valid solutions. Some solutions may be extraneous or outside the interval, so checking each candidate solution against the domain ensures correctness.
Recommended video:
Finding the Domain of an Equation
Related Practice
Textbook Question
555
views
Textbook Question
In Exercises 85β96, use a calculator to solve each equation, correct to four decimal places, on the interval [0, 2π ). sin x = 0.8246
458
views
Textbook Question
In Exercises 85β96, use a calculator to solve each equation, correct to four decimal places, on the interval [0, 2π ). cos x = οΉ£ 2/5
446
views
Textbook Question
In Exercises 63β84, use an identity to solve each equation on the interval [0, 2π ). sin ( x + π /4) + sin ( x - π /4 ) = 1
443
views
Textbook Question
In Exercises 85β96, use a calculator to solve each equation, correct to four decimal places, on the interval [0, 2π ). tan x = οΉ£3
472
views
Textbook Question
In Exercises 63β84, use an identity to solve each equation on the interval [0, 2π ). sin 2x cos x + cos 2x sin x = β 2/2
478
views
