Solving 2sin(θ) - √2 = 0 Find All Solutions In Radians

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Introduction

In this comprehensive guide, we will delve into the process of finding all solutions to the trigonometric equation 2sin(θ) - √2 = 0. This equation falls under the category of trigonometric equations, which are equations that involve trigonometric functions such as sine, cosine, tangent, and their reciprocals. Solving trigonometric equations often requires a deep understanding of trigonometric identities, the unit circle, and the periodic nature of trigonometric functions. Our main keyword for this section is solving trigonometric equations, and we will emphasize the importance of understanding fundamental trigonometric concepts to tackle such problems effectively. We will explore the step-by-step approach to isolate the trigonometric function, determine the reference angle, and identify all possible solutions within a given interval or the entire domain. Moreover, we will address the concept of general solutions, which incorporate the periodic nature of trigonometric functions to express all possible solutions. By mastering the techniques presented in this guide, you will gain confidence in solving a wide range of trigonometric equations and appreciate their applications in various fields, including physics, engineering, and mathematics.

Trigonometric equations play a crucial role in modeling periodic phenomena, such as oscillations, waves, and harmonic motion. Understanding how to solve these equations is essential for analyzing and predicting the behavior of these phenomena. This guide provides a thorough explanation of the methods used to solve the equation 2sin(θ) - √2 = 0, covering the underlying principles and practical steps involved. We will explore the use of the unit circle, trigonometric identities, and algebraic manipulations to find solutions. By the end of this guide, you will have a solid foundation in solving trigonometric equations and be able to apply these skills to more complex problems. Our focus is on providing a clear and concise explanation, making it accessible to students and enthusiasts alike. The techniques discussed here are applicable to a wide range of trigonometric equations, making this guide a valuable resource for anyone studying trigonometry or related fields. This comprehensive guide aims to equip you with the necessary tools and knowledge to confidently tackle trigonometric equations and appreciate their significance in various scientific and engineering applications. Through a step-by-step approach, we will unravel the complexities of solving trigonometric equations, ensuring that you not only understand the process but also the underlying concepts that make it work.

Isolating the Sine Function

Our first crucial step in finding solutions to the trigonometric equation 2sin(θ) - √2 = 0 involves isolating the sine function. This is a fundamental algebraic technique that simplifies the equation and allows us to work directly with the trigonometric term. By isolating the sine function, we are essentially rearranging the equation to have the term sin(θ) by itself on one side. This process mirrors the way we solve basic algebraic equations, where we isolate the variable. Our main keyword for this section is isolating sine function, and we will break down the process into clear, manageable steps. We begin by adding √2 to both sides of the equation, which cancels out the -√2 term on the left side and moves the constant to the right side. This results in the equation 2sin(θ) = √2. The next step is to divide both sides of the equation by 2, which isolates the sine function completely. This yields the equation sin(θ) = √2 / 2. This equation is now in a form that allows us to directly identify the angles θ that satisfy it. The importance of this step cannot be overstated; isolating the trigonometric function is the foundation for solving trigonometric equations.

The algebraic manipulation involved in isolating the sine function is a straightforward yet essential part of the solution process. By adding √2 to both sides and then dividing by 2, we transform the original equation into a much simpler form. This simplified form, sin(θ) = √2 / 2, directly relates the sine of the angle θ to a specific value. This direct relationship enables us to use our knowledge of the unit circle and trigonometric values to find the angles that satisfy the equation. The act of isolating the trigonometric function is a common strategy in solving various types of trigonometric equations, making it a valuable technique to master. Understanding this step allows us to focus on the core trigonometric concepts involved in finding the solutions. Without isolating the sine function, it would be significantly more challenging to determine the possible values of θ. This isolation process not only simplifies the equation but also sets the stage for the subsequent steps in finding the complete solution set. Our detailed explanation of this step aims to provide a clear understanding of the algebraic manipulation involved and its critical role in solving the equation.

Determining the Reference Angle

Once we have isolated the sine function and obtained the equation sin(θ) = √2 / 2, the next critical step is to determine the reference angle. The reference angle, denoted as θ', is the acute angle formed by the terminal side of the angle θ and the x-axis. It is always a positive angle less than 90 degrees (or π/2 radians). Identifying the reference angle is essential because it allows us to relate the sine value to angles in the first quadrant, where trigonometric values are well-known. Our main keyword for this section is reference angle, and we will explore its significance in solving trigonometric equations. The reference angle helps us find all angles in different quadrants that have the same sine value (either positive or negative). For the equation sin(θ) = √2 / 2, we need to recall the angles whose sine value is √2 / 2. We know from the unit circle and trigonometric tables that sin(π/4) = √2 / 2. Therefore, the reference angle θ' in this case is π/4 radians. This means that the angles we are looking for will have a reference angle of π/4.

The concept of the reference angle is a powerful tool in trigonometry because it simplifies the process of finding angles with specific trigonometric values in different quadrants. By knowing the reference angle, we can use the properties of sine, cosine, and tangent in each quadrant to determine the possible solutions. In this case, since sin(θ) = √2 / 2, which is positive, we know that the solutions for θ must lie in the first and second quadrants, where the sine function is positive. The reference angle π/4 helps us find these angles. In the first quadrant, the angle is simply the reference angle itself, which is π/4. In the second quadrant, the angle is found by subtracting the reference angle from π, giving us π - π/4 = 3π/4. Thus, the reference angle acts as a building block for finding all solutions within the interval [0, 2π). Understanding the reference angle and its relationship to the unit circle is crucial for solving trigonometric equations accurately and efficiently. Our detailed explanation aims to highlight the importance of the reference angle in the solution process and provide a clear method for determining it.

Identifying Solutions in the Interval [0, 2π)

Having determined the reference angle as π/4 radians for the equation sin(θ) = √2 / 2, our next task is to identify all the solutions within the interval [0, 2π). This interval represents one full rotation around the unit circle. Since the sine function is positive in the first and second quadrants, we will focus on finding angles in these quadrants that have a reference angle of π/4. Our main keyword for this section is solutions in [0, 2π), and we will provide a step-by-step approach to find these specific solutions. In the first quadrant, the solution is straightforward: it is simply the reference angle itself, which is π/4. In the second quadrant, to find the angle with a reference angle of π/4, we subtract π/4 from π. This gives us π - π/4 = 3π/4. Therefore, within the interval [0, 2π), there are two solutions to the equation sin(θ) = √2 / 2: θ = π/4 and θ = 3π/4. These angles correspond to points on the unit circle where the y-coordinate (which represents the sine value) is √2 / 2.

Finding the solutions within the interval [0, 2π) is a crucial step in solving trigonometric equations because it gives us the fundamental angles that satisfy the equation within one complete cycle of the sine function. By understanding the behavior of the sine function in each quadrant and using the reference angle, we can efficiently identify these solutions. The unit circle serves as a visual aid in this process, allowing us to see the angles and their corresponding sine values. It is important to remember that these are not the only solutions to the equation; they are merely the solutions within one rotation. The sine function is periodic, meaning its values repeat every 2π radians. Therefore, we will need to consider the general solutions to account for all possible solutions. However, identifying the solutions within [0, 2π) provides a solid foundation for understanding the complete solution set. Our detailed explanation aims to provide a clear understanding of how to use the reference angle and the unit circle to find the specific solutions within the given interval.

Expressing the General Solutions

To find all possible solutions to the equation sin(θ) = √2 / 2, we need to express the general solutions. Since the sine function is periodic with a period of 2π, we can add integer multiples of 2π to our solutions within the interval [0, 2π) to obtain all possible solutions. The general solution represents the infinite set of angles that satisfy the equation. Our main keyword for this section is general solutions, and we will explain how to incorporate the periodicity of the sine function into our answer. We found two solutions in the interval [0, 2π): θ = π/4 and θ = 3π/4. To express the general solutions, we add 2kπ to each of these solutions, where k is any integer (k ∈ Z). This gives us the general solutions:

θ = π/4 + 2kπ, k ∈ Z

θ = 3π/4 + 2kπ, k ∈ Z

These equations represent all possible values of θ that satisfy the equation sin(θ) = √2 / 2. The term 2kπ accounts for the periodic nature of the sine function, ensuring that we capture all angles that have the same sine value.

Expressing the general solutions is the final step in completely solving the trigonometric equation. It demonstrates an understanding of the periodic nature of trigonometric functions and ensures that no possible solution is overlooked. The use of the integer k in the general solution formula allows us to generate an infinite number of solutions, all of which satisfy the original equation. Each integer value of k corresponds to a different rotation around the unit circle. For example, if k = 0, we get the solutions within the interval [0, 2π). If k = 1, we get solutions in the interval [2π, 4π), and so on. The general solution is a compact way of representing all these solutions. It is important to note that the general solutions are not unique; there are multiple ways to express them. However, the key is to capture all possible angles that satisfy the equation. Our detailed explanation aims to provide a clear understanding of how to construct the general solutions and the significance of the periodic term 2kπ.

Conclusion

In conclusion, we have thoroughly explored the process of finding all solutions to the trigonometric equation 2sin(θ) - √2 = 0. We began by isolating the sine function, which led us to the equation sin(θ) = √2 / 2. Then, we determined the reference angle as π/4 radians and identified the solutions within the interval [0, 2π) as θ = π/4 and θ = 3π/4. Finally, we expressed the general solutions as θ = π/4 + 2kπ, k ∈ Z and θ = 3π/4 + 2kπ, k ∈ Z. Our journey through this equation has highlighted the importance of understanding trigonometric identities, the unit circle, and the periodic nature of trigonometric functions. We emphasize the systematic approach of isolating the trigonometric function, finding the reference angle, identifying solutions in the interval [0, 2π), and expressing the general solutions to ensure a complete and accurate solution.

This comprehensive guide has not only demonstrated the steps involved in solving a specific trigonometric equation but also provided a framework for tackling other similar problems. The techniques discussed here are applicable to a wide range of trigonometric equations, making this guide a valuable resource for anyone studying trigonometry or related fields. By mastering the concepts and methods presented, you will be well-equipped to solve trigonometric equations with confidence and appreciate their applications in various areas of science and engineering. We encourage you to practice these techniques with different equations to further solidify your understanding. The ability to solve trigonometric equations is a fundamental skill in mathematics and is essential for understanding many real-world phenomena that exhibit periodic behavior. Our aim has been to provide a clear, concise, and accessible explanation that empowers you to solve trigonometric equations effectively and efficiently.