Solving Trigonometric Equations Find Solutions For 2 Sin Θ - √3 = 0

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Solving trigonometric equations is a fundamental skill in mathematics, with applications ranging from physics and engineering to computer graphics and beyond. This article delves into the process of finding solutions for trigonometric equations within a specified interval, focusing on the equation 2extsinθ3=02 ext{sin} \theta - \sqrt{3} = 0 in the interval [0,2π)[0, 2\pi). We will explore the underlying concepts, step-by-step solutions, and provide insights to enhance your understanding of trigonometric equations.

Before diving into the solution, let's establish a clear understanding of trigonometric equations. A trigonometric equation is an equation that involves trigonometric functions such as sine, cosine, tangent, and their reciprocals. Solving a trigonometric equation means finding the values of the angle (usually denoted by θ\theta or xx) that satisfy the equation. These solutions often represent angles where the trigonometric functions have specific values. For instance, the equation 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0 asks us to find all angles θ\theta within the interval [0,2π)[0, 2\pi) for which the sine of the angle, when multiplied by 2 and then reduced by 3\sqrt{3}, equals zero. This involves understanding the behavior of the sine function across different quadrants and reference angles. Trigonometric equations can have multiple solutions due to the periodic nature of trigonometric functions. The sine function, for example, repeats its values every 2π2\pi radians, meaning that there are infinitely many angles that yield the same sine value. Therefore, when solving these equations, it is crucial to consider the given interval to identify the specific solutions within that range. This article will guide you through the steps necessary to find these solutions effectively, ensuring you grasp the core principles behind solving trigonometric equations.

Solving 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0

The given equation is 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0. Our goal is to find all values of θ\theta in the interval [0,2π)[0, 2\pi) that satisfy this equation. The first step is to isolate the sine function. This involves algebraic manipulation to get sinθ\text{sin} \theta by itself on one side of the equation. Starting with 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0, we add 3\sqrt{3} to both sides of the equation, resulting in 2sinθ=32 \text{sin} \theta = \sqrt{3}. Next, we divide both sides by 2 to isolate sinθ\text{sin} \theta, which gives us sinθ=32\text{sin} \theta = \frac{\sqrt{3}}{2}. Now that we have isolated sinθ\text{sin} \theta, we need to find the angles θ\theta in the interval [0,2π)[0, 2\pi) where the sine function equals 32\frac{\sqrt{3}}{2}. We know that the sine function represents the y-coordinate on the unit circle. Therefore, we are looking for points on the unit circle where the y-coordinate is 32\frac{\sqrt{3}}{2}. Remembering the special angles and their sine values, we recall that sin(π3)=32\text{sin}(\frac{\pi}{3}) = \frac{\sqrt{3}}{2}. This gives us one solution, θ=π3\theta = \frac{\pi}{3}. However, we must also consider that sine is positive in both the first and second quadrants. In the second quadrant, the reference angle for π3\frac{\pi}{3} is ππ3=2π3\pi - \frac{\pi}{3} = \frac{2\pi}{3}. Thus, sin(2π3)=32\text{sin}(\frac{2\pi}{3}) = \frac{\sqrt{3}}{2} as well. Therefore, the solutions to the equation 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0 in the interval [0,2π)[0, 2\pi) are θ=π3\theta = \frac{\pi}{3} and θ=2π3\theta = \frac{2\pi}{3}.

Identifying Solutions in the Interval [0,2π)[0, 2\pi)

To find the solutions of the equation 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0 within the interval [0,2π)[0, 2\pi), we first need to isolate sinθ\text{sin} \theta. As we determined earlier, this leads to sinθ=32\text{sin} \theta = \frac{\sqrt{3}}{2}. Now, we focus on finding the angles θ\theta in the specified interval where the sine function takes this value. The interval [0,2π)[0, 2\pi) represents one full revolution around the unit circle, starting from 0 radians and ending just before 2π2\pi radians. We know that sinθ\text{sin} \theta corresponds to the y-coordinate on the unit circle. Therefore, we are looking for angles where the y-coordinate is 32\frac{\sqrt{3}}{2}. From our knowledge of special angles, we know that sin(π3)=32\text{sin}(\frac{\pi}{3}) = \frac{\sqrt{3}}{2}. This gives us one solution, θ=π3\theta = \frac{\pi}{3}, which lies in the first quadrant. To find other solutions, we need to consider the quadrants where sine is also positive. Sine is positive in both the first and second quadrants. In the second quadrant, the reference angle for π3\frac{\pi}{3} is calculated by subtracting π3\frac{\pi}{3} from π\pi. This gives us ππ3=2π3\pi - \frac{\pi}{3} = \frac{2\pi}{3}. Therefore, sin(2π3)=32\text{sin}(\frac{2\pi}{3}) = \frac{\sqrt{3}}{2} as well, providing us with another solution, θ=2π3\theta = \frac{2\pi}{3}. Since we have covered both quadrants where sine is positive within the interval [0,2π)[0, 2\pi), we have found all the solutions. Thus, the solutions to the equation 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0 in the interval [0,2π)[0, 2\pi) are θ=π3\theta = \frac{\pi}{3} and θ=2π3\theta = \frac{2\pi}{3}. This methodical approach ensures that we identify all possible solutions within the given interval by considering the properties of the sine function and its behavior in different quadrants.

General Solutions and the Unit Circle

Understanding the general solutions of trigonometric equations and the unit circle is crucial for solving a wide range of trigonometric problems. The unit circle is a circle with a radius of 1 centered at the origin of the Cartesian coordinate system. It provides a visual representation of trigonometric functions, where the coordinates of any point on the circle are given by (cosθ,sinθ)(\text{cos} \theta, \text{sin} \theta), with θ\theta being the angle formed by the positive x-axis and the line segment connecting the origin to the point. The unit circle helps us understand the periodic nature of trigonometric functions. For example, the sine function repeats its values every 2π2\pi radians because after a full rotation around the circle, we return to the same point and the same sine value. This periodicity is why trigonometric equations often have infinitely many solutions. To find the general solutions, we first identify the solutions within a single period (usually [0,2π)[0, 2\pi)). Then, we add integer multiples of the period to these solutions to account for all possible solutions. For the sine function, the general solution can be written as θ=θ0+2nπ\theta = \theta_0 + 2n\pi and θ=(πθ0)+2nπ\theta = (\pi - \theta_0) + 2n\pi, where θ0\theta_0 is a particular solution within the interval [0,2π)[0, 2\pi) and nn is an integer. In our case, for the equation sinθ=32\text{sin} \theta = \frac{\sqrt{3}}{2}, we found solutions θ=π3\theta = \frac{\pi}{3} and θ=2π3\theta = \frac{2\pi}{3} within the interval [0,2π)[0, 2\pi). Therefore, the general solutions are θ=π3+2nπ\theta = \frac{\pi}{3} + 2n\pi and θ=2π3+2nπ\theta = \frac{2\pi}{3} + 2n\pi, where nn is an integer. Understanding the general solutions allows us to find all possible angles that satisfy the equation, not just those within a specific interval. The unit circle provides a visual aid for this process, helping us see how the sine and cosine values repeat as we rotate around the circle.

Expressing solutions in radians is essential in trigonometry and calculus because radians provide a natural and consistent way to measure angles. Radians are based on the radius of a circle, where one radian is defined as the angle subtended at the center of the circle by an arc equal in length to the radius. This contrasts with degrees, which are an arbitrary division of a circle into 360 parts. The relationship between radians and degrees is given by π radians=180\pi \text{ radians} = 180^\circ. This conversion factor is crucial for switching between the two units. In the context of trigonometric equations, solutions are typically expressed in radians because many formulas and theorems in calculus and advanced mathematics are simpler and more elegant when using radians. For example, the derivative of sin(x)\text{sin}(x) is cos(x)\text{cos}(x) only when xx is in radians. In our example, the solutions to the equation 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0 within the interval [0,2π)[0, 2\pi) were found to be θ=π3\theta = \frac{\pi}{3} and θ=2π3\theta = \frac{2\pi}{3}. These solutions are already expressed in radians, making them directly applicable in further calculations or analyses. When solving trigonometric equations, it is important to remember the common radian values for special angles, such as 0,π6,π4,π3,π2,π,3π2, and 2π0, \frac{\pi}{6}, \frac{\pi}{4}, \frac{\pi}{3}, \frac{\pi}{2}, \pi, \frac{3\pi}{2}, \text{ and } 2\pi. These angles and their corresponding sine, cosine, and tangent values are fundamental and will frequently appear in trigonometric problems. Proficiency in working with radians is a key skill for anyone studying trigonometry and related fields.

In summary, we have thoroughly addressed the process of finding solutions for the trigonometric equation 2sinθ3=02 \text{sin} \theta - \sqrt{3} = 0 within the interval [0,2π)[0, 2\pi). By isolating the sine function, identifying reference angles, and considering the quadrants where sine is positive, we determined the solutions to be θ=π3\theta = \frac{\pi}{3} and θ=2π3\theta = \frac{2\pi}{3}. We also emphasized the importance of understanding the unit circle, general solutions, and expressing angles in radians. Mastering these concepts is crucial for tackling a wide variety of trigonometric problems. Trigonometric equations play a vital role in numerous fields, including physics, engineering, and computer science. Being able to solve these equations accurately and efficiently is a valuable skill. This article has provided a comprehensive guide to the process, equipping you with the knowledge and techniques to confidently approach similar problems. Remember to practice regularly and apply these concepts to different scenarios to solidify your understanding. With consistent effort, you will become proficient in solving trigonometric equations and appreciate their significance in various applications. The ability to find solutions for trigonometric equations is not just a mathematical exercise; it is a fundamental skill that opens doors to deeper insights and problem-solving capabilities in many areas of science and technology.

Solutions: θ=π3,2π3\theta = \frac{\pi}{3}, \frac{2\pi}{3}