Is Π/12 A Solution For 2cos²(4x) - 1 = 0? A Detailed Analysis

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Introduction

In this article, we will delve into the question of whether the value π/12 is a solution for the trigonometric equation 2cos²(4x) - 1 = 0. This is a fundamental problem in trigonometry that requires a strong understanding of trigonometric identities and equation-solving techniques. We will break down the problem step-by-step, providing a detailed explanation of each step involved. Our goal is to not only provide a definitive answer but also to enhance your comprehension of the underlying principles of trigonometry. Through this exploration, we aim to equip you with the skills and knowledge to tackle similar problems with confidence. This comprehensive analysis will cover the necessary background, the detailed solution, and a discussion of the implications and broader applications of the concepts involved. So, let's embark on this journey to unravel the mysteries of trigonometric equations and solutions.

Background: Trigonometric Identities and Equations

Before we directly tackle the problem, it's crucial to establish a solid foundation by reviewing essential trigonometric identities and the general approach to solving trigonometric equations. Trigonometric identities are equations that hold true for all values of the variables involved. They are the fundamental building blocks for simplifying and manipulating trigonometric expressions. One of the key identities we will use in this problem is the double-angle formula for cosine. The identity cos(2θ) = 2cos²(θ) - 1 is particularly relevant because it directly relates to the given equation. Understanding this identity is paramount as it allows us to transform the equation into a more manageable form. In the context of solving trigonometric equations, our goal is to find the values of the variable (in this case, x) that satisfy the equation. This often involves using algebraic manipulations and trigonometric identities to isolate the variable. It's also important to consider the periodic nature of trigonometric functions, which means that there can be infinitely many solutions. When solving trigonometric equations, we usually find general solutions, which encompass all possible solutions by adding integer multiples of the period of the function. Thus, a thorough understanding of these concepts is essential for successfully navigating the problem at hand.

Detailed Solution: Verifying π/12 as a Solution

To determine whether π/12 is a solution for the equation 2cos²(4x) - 1 = 0, we will substitute x = π/12 into the equation and verify if the equation holds true. This process involves a series of steps that include substitution, simplification using trigonometric identities, and evaluation of the trigonometric function. First, we substitute x = π/12 into the equation, which gives us 2cos²(4(π/12)) - 1 = 0. Next, we simplify the argument of the cosine function. Multiplying 4 by π/12, we get 4(π/12) = π/3. So, the equation becomes 2cos²(π/3) - 1 = 0. Now, we need to evaluate cos(π/3). Recall that π/3 radians is equal to 60 degrees, and cos(π/3) = 1/2. Substituting this value into the equation, we get 2(1/2)² - 1 = 0. Simplifying further, we have 2(1/4) - 1 = 0, which leads to 1/2 - 1 = 0. Finally, we evaluate the expression to get -1/2 = 0. Since -1/2 is not equal to 0, the equation does not hold true for x = π/12. Therefore, we can conclude that π/12 is not a solution for the given equation. This detailed step-by-step analysis clearly demonstrates the process of verifying a potential solution for a trigonometric equation.

Exploring Alternative Solutions

Now that we have established that π/12 is not a solution for the equation 2cos²(4x) - 1 = 0, it's beneficial to explore the actual solutions to the equation. This involves a more comprehensive approach to solving trigonometric equations, utilizing trigonometric identities and algebraic manipulation. The given equation, 2cos²(4x) - 1 = 0, can be rewritten using the double-angle identity for cosine, which states that cos(2θ) = 2cos²(θ) - 1. By letting θ = 4x, we can rewrite the equation as cos(8x) = 0. To solve this equation, we need to find the values of 8x for which the cosine function is equal to zero. We know that cos(θ) = 0 when θ = π/2 + nπ, where n is an integer. Therefore, we have 8x = π/2 + nπ. To find the values of x, we divide both sides of the equation by 8, which gives us x = (π/2 + nπ)/8. Simplifying this expression, we get x = π/16 + nπ/8, where n is an integer. This general solution represents all possible values of x that satisfy the equation. By substituting different integer values for n, we can find specific solutions. For example, when n = 0, we get x = π/16; when n = 1, we get x = 3π/16; and so on. These values represent the actual solutions to the equation, providing a clearer understanding of the solution set.

Implications and Broader Applications

Understanding the process of solving trigonometric equations and verifying solutions has significant implications and broader applications in various fields. The techniques we've employed, such as using trigonometric identities and finding general solutions, are fundamental in many areas of mathematics, physics, and engineering. In mathematics, these skills are essential for calculus, differential equations, and complex analysis. Many problems in calculus involve finding the solutions of trigonometric equations, and a solid understanding of these concepts is crucial for success in these areas. In physics, trigonometric functions are used extensively to model oscillatory motion, wave phenomena, and electromagnetic fields. Solving trigonometric equations is often necessary to determine the characteristics of these systems, such as frequencies and amplitudes. For instance, in mechanical oscillations, the position of a mass attached to a spring can be described by a trigonometric function, and finding the times at which the mass reaches certain positions involves solving trigonometric equations. Similarly, in electrical engineering, alternating current circuits are analyzed using trigonometric functions, and solving related equations is vital for circuit design and analysis. These examples highlight the wide applicability of the skills and knowledge gained from solving trigonometric equations. Thus, mastering these techniques is not just an academic exercise but a valuable tool for tackling real-world problems in diverse fields.

Conclusion: π/12 is Not a Solution

In summary, through a detailed step-by-step analysis, we have conclusively determined that the value π/12 is not a solution for the equation 2cos²(4x) - 1 = 0. We began by substituting x = π/12 into the equation and carefully simplifying the expression, which ultimately led to the result -1/2 = 0. This contradiction clearly demonstrates that π/12 does not satisfy the equation. Furthermore, we went beyond merely verifying the given value and explored the general solution to the equation. By using the double-angle identity for cosine and algebraic manipulation, we found the general solution to be x = π/16 + nπ/8, where n is an integer. This solution set provides a comprehensive understanding of all possible values of x that satisfy the equation. This exploration underscores the importance of not only verifying potential solutions but also understanding the broader solution landscape. The process of solving trigonometric equations and verifying solutions is a fundamental skill in mathematics with far-reaching applications in various scientific and engineering disciplines. By mastering these techniques, we equip ourselves with the tools to tackle a wide array of problems and gain a deeper appreciation for the beauty and utility of trigonometry.