Finding The X-intercept Of Y = Tan(x - 5π/6) A Comprehensive Guide

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In the realm of mathematics, understanding the behavior of functions is crucial. Among the various aspects of a function's behavior, xx-intercepts hold a special significance. An xx-intercept is a point where the graph of a function intersects the xx-axis. At this point, the yy-coordinate is always zero. In simpler terms, it's the value of xx for which the function's output, yy, becomes zero. Finding xx-intercepts is not just a mathematical exercise; it has practical applications in various fields, including physics, engineering, and economics. For instance, in physics, the xx-intercept of a projectile's trajectory can represent the point where it hits the ground. In economics, it might represent the break-even point where revenue equals cost.

To find the xx-intercepts of a function, we set y=0y = 0 and solve for xx. This might involve algebraic manipulation, trigonometric identities, or other techniques depending on the complexity of the function. The solutions we obtain are the xx-coordinates of the xx-intercepts. The xx-intercepts are usually expressed as ordered pairs (x,0)(x, 0). The process of finding xx-intercepts can sometimes be challenging, especially for complex functions. However, understanding the fundamental principles and utilizing appropriate techniques can make the task manageable. This article will delve into the specific case of finding the xx-intercepts of a tangent function, illustrating the steps and concepts involved in solving such problems. By mastering this process, you'll gain a deeper understanding of trigonometric functions and their graphical representations.

The tangent function, denoted as tan(x)\tan(x), is a fundamental trigonometric function that plays a vital role in various mathematical and scientific applications. It's defined as the ratio of the sine function to the cosine function: tan(x)=sin(x)cos(x)\tan(x) = \frac{\sin(x)}{\cos(x)}. The tangent function has several key characteristics that distinguish it from other trigonometric functions like sine and cosine. One notable feature is its periodicity. The tangent function repeats its values every π\pi radians, unlike sine and cosine, which repeat every 2π2\pi radians. This means that tan(x)=tan(x+nπ)\tan(x) = \tan(x + n\pi) for any integer nn. Another important characteristic is the presence of vertical asymptotes. The tangent function is undefined at points where cos(x)=0\cos(x) = 0, which occurs at x=(2n+1)π2x = \frac{(2n + 1)\pi}{2}, where nn is an integer. At these points, the function approaches infinity, resulting in vertical asymptotes on the graph.

The given function, y=tan(x5π6)y = \tan(x - \frac{5\pi}{6}), is a transformation of the basic tangent function. The term (x5π6)(x - \frac{5\pi}{6}) inside the tangent function represents a horizontal phase shift. Specifically, the graph of y=tan(x)y = \tan(x) is shifted to the right by 5π6\frac{5\pi}{6} units. This shift affects the position of the vertical asymptotes and the xx-intercepts of the function. Understanding the effect of this phase shift is crucial for accurately determining the xx-intercepts of the given function. To find the xx-intercepts, we need to determine the values of xx for which y=0y = 0. This involves solving the equation tan(x5π6)=0\tan(x - \frac{5\pi}{6}) = 0. By carefully considering the properties of the tangent function and the phase shift, we can systematically find the solutions and identify the xx-intercepts of the function. This process demonstrates the interplay between algebraic manipulation and trigonometric concepts in solving mathematical problems.

The primary goal is to find the xx-intercepts of the function y=tan(x5π6)y = \tan(x - \frac{5\pi}{6}). As we discussed earlier, xx-intercepts occur where the function's value, yy, is equal to zero. Therefore, we need to solve the equation tan(x5π6)=0\tan(x - \frac{5\pi}{6}) = 0. The tangent function equals zero at integer multiples of π\pi. That is, tan(θ)=0\tan(\theta) = 0 when θ=nπ\theta = n\pi, where nn is an integer. Applying this knowledge to our equation, we can set the argument of the tangent function equal to nπn\pi: $x - \frac5\pi}{6} = n\pi$ Next, we need to isolate xx to find the values that satisfy this equation. We can do this by adding 5π6\frac{5\pi}{6} to both sides of the equation $x = n\pi + \frac{5\pi6}$ This equation gives us a general solution for xx in terms of nn. To find specific xx-intercepts, we can substitute different integer values for nn. For example, when n=0n = 0, we have $x = 0\pi + \frac{5\pi6} = \frac{5\pi}{6}$ This gives us one xx-intercept at x=5π6x = \frac{5\pi}{6}. We can also try other values of nn to find additional xx-intercepts. When n=1n = -1, we have $x = -1\pi + \frac{5\pi{6} = -\frac{\pi}{6}$ This gives us another xx-intercept at x=π6x = -\frac{\pi}{6}. By substituting different integer values for nn, we can generate a series of xx-intercepts. Each of these values represents a point where the graph of the function intersects the xx-axis. The step-by-step approach ensures that we systematically find all possible xx-intercepts within a given domain or interval. This method highlights the importance of understanding the properties of trigonometric functions and applying algebraic techniques to solve equations.

Now that we have a general solution for the xx-intercepts, x=nπ+5π6x = n\pi + \frac{5\pi}{6}, we can use this to identify the correct answer from the given options. The options are presented as ordered pairs (x,0)(x, 0), where xx is the xx-coordinate of the xx-intercept. We need to find the option that matches one of the values generated by our general solution. Let's examine the options:

  • A. (2π3,0)\left(-\frac{2\pi}{3}, 0\right): We need to check if there is an integer nn such that 2π3=nπ+5π6-\frac{2\pi}{3} = n\pi + \frac{5\pi}{6}. Subtracting 5π6\frac{5\pi}{6} from both sides, we get 2π35π6=nπ-\frac{2\pi}{3} - \frac{5\pi}{6} = n\pi, which simplifies to 9π6=nπ-\frac{9\pi}{6} = n\pi or 32=n-\frac{3}{2} = n. Since 32-\frac{3}{2} is not an integer, this option is not an xx-intercept.
  • B. (π3,0)\left(-\frac{\pi}{3}, 0\right): Similarly, we check if π3=nπ+5π6-\frac{\pi}{3} = n\pi + \frac{5\pi}{6}. Subtracting 5π6\frac{5\pi}{6} from both sides, we get π35π6=nπ-\frac{\pi}{3} - \frac{5\pi}{6} = n\pi, which simplifies to 7π6=nπ-\frac{7\pi}{6} = n\pi or 76=n-\frac{7}{6} = n. Since 76-\frac{7}{6} is not an integer, this option is also not an xx-intercept.
  • C. (π6,0)\left(\frac{\pi}{6}, 0\right): We check if π6=nπ+5π6\frac{\pi}{6} = n\pi + \frac{5\pi}{6}. Subtracting 5π6\frac{5\pi}{6} from both sides, we get π65π6=nπ\frac{\pi}{6} - \frac{5\pi}{6} = n\pi, which simplifies to 4π6=nπ-\frac{4\pi}{6} = n\pi or 23=n-\frac{2}{3} = n. Since 23-\frac{2}{3} is not an integer, this option is not an xx-intercept.
  • D. (5π6,0)\left(\frac{5\pi}{6}, 0\right): We check if 5π6=nπ+5π6\frac{5\pi}{6} = n\pi + \frac{5\pi}{6}. Subtracting 5π6\frac{5\pi}{6} from both sides, we get 0=nπ0 = n\pi, which implies n=0n = 0. Since 0 is an integer, this option is an xx-intercept.

Therefore, the correct answer is D. (5π6,0)\left(\frac{5\pi}{6}, 0\right). This systematic approach demonstrates how to use the general solution to verify the given options and identify the correct xx-intercept. It reinforces the importance of understanding the properties of trigonometric functions and applying algebraic techniques to solve problems.

In this comprehensive guide, we've explored the process of finding the xx-intercepts of a tangent function, specifically y=tan(x5π6)y = \tan(x - \frac{5\pi}{6}). We began by understanding the significance of xx-intercepts as points where the graph of a function intersects the xx-axis, representing the values of xx for which the function's output is zero. This concept has broad applications across various fields, highlighting the practical importance of mastering this skill.

We then delved into the characteristics of the tangent function, including its periodicity and the presence of vertical asymptotes. Understanding the transformation applied to the basic tangent function, a horizontal phase shift of 5π6\frac{5\pi}{6}, was crucial in accurately determining the xx-intercepts. By setting the function equal to zero and solving for xx, we derived a general solution, x=nπ+5π6x = n\pi + \frac{5\pi}{6}, where nn is an integer. This general solution allowed us to generate a series of xx-intercepts by substituting different integer values for nn.

Finally, we applied our general solution to identify the correct xx-intercept from the given options. By systematically checking each option, we verified that (5π6,0)\left(\frac{5\pi}{6}, 0\right) is indeed an xx-intercept of the function. This step-by-step approach reinforces the importance of combining algebraic manipulation with a solid understanding of trigonometric properties.

Mastering the process of finding xx-intercepts, especially for trigonometric functions, is a valuable skill in mathematics and its applications. It requires a combination of conceptual understanding, algebraic proficiency, and careful attention to detail. By following the steps outlined in this guide, you can confidently tackle similar problems and deepen your understanding of trigonometric functions and their graphical representations. The ability to find xx-intercepts not only enhances your problem-solving skills but also provides a foundation for more advanced mathematical concepts and applications.