Solving $4 an heta - 4 = 0$: A Trigonometric Solution

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Let's dive into the world of trigonometry and tackle the equation 4anheta4=04 an heta - 4 = 0. This article will guide you through a step-by-step solution, ensuring you understand each stage of the process. We'll cover the basics of trigonometric functions, how to isolate the variable, and finally, how to find the solutions within the given interval. If you've ever wondered how to solve trigonometric equations, you're in the right place! This equation might seem daunting at first, but with a clear, methodical approach, we can easily find the values of θ\theta that satisfy the condition. Remember, trigonometry is all about understanding the relationships between angles and sides in triangles, and equations like this help us explore those relationships further. So, grab your calculator (or your mental math skills!) and let's get started on unraveling this trigonometric puzzle.

Understanding the Tangent Function

Before we jump into solving the equation, it's essential to have a solid grasp of the tangent function. The tangent (tan) function is one of the primary trigonometric functions, relating an angle in a right-angled triangle to the ratio of the opposite side to the adjacent side. In mathematical terms, if θ\theta is an angle in a right triangle, then tan(θ)=oppositeadjacent\tan(\theta) = \frac{\text{opposite}}{\text{adjacent}}. Understanding this fundamental definition is crucial because it forms the basis for solving equations involving the tangent function. The tangent function also has a graphical representation, which is a periodic function with vertical asymptotes. These asymptotes occur because the tangent function is undefined when the adjacent side of the triangle is zero. This occurs at angles that are odd multiples of π2\frac{\pi}{2}. The period of the tangent function is π\pi, meaning that its values repeat every π\pi radians. The tangent function is positive in the first and third quadrants and negative in the second and fourth quadrants. This periodicity and the sign of the tangent function in different quadrants will be vital when we find all possible solutions for our equation. The tangent function's behavior can be visualized using the unit circle, where the tangent value corresponds to the slope of the line connecting the origin to a point on the circle. Knowing these properties of the tangent function will help us solve the equation efficiently and accurately.

Isolating the Tangent Function

Our primary goal is to isolate the tanθ\tan \theta term in the equation 4tanθ4=04 \tan \theta - 4 = 0. This involves performing algebraic manipulations to get the tangent function by itself on one side of the equation. The first step is to add 4 to both sides of the equation. This gives us 4tanθ=44 \tan \theta = 4. Next, we need to divide both sides of the equation by 4 to completely isolate tanθ\tan \theta. Doing so, we get tanθ=1\tan \theta = 1. This simplified equation tells us that we are looking for angles θ\theta where the tangent function equals 1. Isolating the trigonometric function is a crucial step in solving any trigonometric equation. By doing this, we reduce the problem to finding the angles that satisfy a specific trigonometric value, which is often more straightforward. In this case, we've transformed the original equation into a much simpler form, making it easier to identify the solutions. This process of isolating the trigonometric function is a common technique applicable to solving a wide range of trigonometric equations. Understanding this step thoroughly will greatly improve your ability to solve similar problems. Now that we have isolated tanθ\tan \theta, we can move on to finding the specific values of θ\theta that satisfy the condition tanθ=1\tan \theta = 1.

Finding the Principal Solution

Now that we have the equation tanθ=1\tan \theta = 1, we need to find the angles θ\theta that satisfy this condition. To begin, we'll find the principal solution, which is the solution within the interval (π2,π2)(-\frac{\pi}{2}, \frac{\pi}{2}). The principal value for θ\theta where tanθ=1\tan \theta = 1 is θ=π4\theta = \frac{\pi}{4}. This is because in a right-angled triangle, the tangent of an angle is 1 when the opposite and adjacent sides are equal, which occurs in a 45-45-90 triangle, where the angle is π4\frac{\pi}{4} radians or 45 degrees. You can visualize this on the unit circle, where the slope of the line connecting the origin to the point on the circle is 1 at π4\frac{\pi}{4}. Knowing the principal solution is essential because it serves as the reference point for finding all other solutions within the given interval. The principal solution is a fundamental concept in trigonometry, and mastering how to find it will significantly help in solving various trigonometric equations. In this context, π4\frac{\pi}{4} is the angle within the principal interval where the tangent function equals 1. This angle will be the basis for identifying other angles within the given range of 0θ<2π0 \leq \theta < 2\pi that also satisfy the equation. So, now that we have the principal solution, we can explore how the periodic nature of the tangent function helps us find additional solutions.

Determining All Solutions in the Given Interval

Since the tangent function has a period of π\pi, it repeats its values every π\pi radians. This means that if tanθ=1\tan \theta = 1 for θ=π4\theta = \frac{\pi}{4}, it will also be 1 for angles that are π\pi radians away. To find all solutions in the interval 0θ<2π0 \leq \theta < 2\pi, we add multiples of π\pi to the principal solution until we exceed the interval. Starting with the principal solution θ=π4\theta = \frac{\pi}{4}, we add π\pi to find another solution: π4+π=5π4\frac{\pi}{4} + \pi = \frac{5\pi}{4}. This angle also lies within our interval of 0θ<2π0 \leq \theta < 2\pi. If we add another π\pi, we get 5π4+π=9π4\frac{5\pi}{4} + \pi = \frac{9\pi}{4}, which is greater than 2π2\pi, so it's outside our interval. Therefore, the solutions to the equation 4tanθ4=04 \tan \theta - 4 = 0 in the interval 0θ<2π0 \leq \theta < 2\pi are θ=π4\theta = \frac{\pi}{4} and θ=5π4\theta = \frac{5\pi}{4}. This process highlights the importance of understanding the periodicity of trigonometric functions. By knowing the period, we can systematically find all solutions within a specified interval. In summary, we first found the principal solution and then used the periodicity of the tangent function to identify additional solutions. This approach is crucial for solving trigonometric equations accurately and efficiently. Now, let's reiterate our final answers to ensure clarity and comprehension.

Final Solutions

To recap, we set out to solve the trigonometric equation 4tanθ4=04 \tan \theta - 4 = 0 for 0θ<2π0 \leq \theta < 2\pi. Through a step-by-step process, we first isolated the tangent function, then found the principal solution, and finally, used the periodic nature of the tangent function to determine all solutions within the given interval. Our final solutions are θ=π4\theta = \frac{\pi}{4} and θ=5π4\theta = \frac{5\pi}{4}. These are the angles within the range of 0 to 2π2\pi for which the equation 4tanθ4=04 \tan \theta - 4 = 0 holds true. It’s worth noting that these solutions correspond to the points on the unit circle where the ratio of the sine to cosine is equal to 1. Visualizing these angles on the unit circle can further solidify your understanding of the solution. By mastering the techniques used in this solution, you can confidently tackle similar trigonometric equations. Remember to always isolate the trigonometric function, find the principal solution, and then use the periodicity to find all solutions within the specified interval. Practice is key to mastering these concepts, so keep solving problems and exploring the fascinating world of trigonometry!

In conclusion, we have successfully solved the equation 4tanθ4=04 \tan \theta - 4 = 0 for 0θ<2π0 \leq \theta < 2\pi, finding the solutions θ=π4\theta = \frac{\pi}{4} and θ=5π4\theta = \frac{5\pi}{4}. This exercise demonstrates the importance of understanding trigonometric functions and their properties. For more information on trigonometric functions and their applications, you can visit Khan Academy's Trigonometry Section.