/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 16 Approximate the point of interse... [FREE SOLUTION] | 91Ó°ÊÓ

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Approximate the point of intersection of the graphs of \(f\) and \(g .\) Then solve the equation \(f(x)=g(x)\) algebraically to verify your approximation. $$\begin{aligned} &f(x)=\log _{3} x\\\ &g(x)=2 \end{aligned}$$ (GRAPH CANNOT COPY)

Short Answer

Expert verified
The point of intersection of the graphs of \(f\) and \(g\) is at \(x=9\).

Step by step solution

01

Approximation of the intersection point

By observing the graphs of \(f(x)=\log_{3}x\) and \(g(x)=2\), it can be noticed that they intersect near \(x=9\). This is an approximation and the accurate value must be calculated algebraically.
02

Solve the equation \(f(x)=g(x)\) algebraically

To find the exact point of intersection, the two functions need to be set equal to each other and solve for \(x\). That means, \(\log_{3}x = 2\). The base-3 logarithm of \(x\) is equal to 2, which means \(3^{2} = x\).
03

Calculate the value of x

On calculating \(3^{2}\), we find \(x=9\). This is the exact value of the point of intersection, which approves our approximation from the graph analysis.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Logarithmic Functions
Logarithmic functions are a fundamental concept in mathematics and appear frequently in various real-world applications. In this exercise, the function is represented by \( f(x) = \log_{3}x \), which denotes the logarithm of \( x \) with base 3. Logarithmic functions are the inverse of exponential functions, meaning if \( y = \log_{3}x \), then \( x = 3^{y} \).

This relationship is key to solving problems involving logarithms as it allows us to convert logarithmic equations into exponential ones. Logarithms are useful for calculations involving exponential growth/decay, and they simplify complex multiplicative operations into additive ones. Understanding the properties of logarithms, such as the change of base formula and log rules like \( \log_{a}(bc) = \log_{a}b + \log_{a}c \), helps in solving equations involving logarithms.

In our example, we set \( \log_{3}x \) equal to 2 to find where two functions intersect. By recognizing that if \( \log_{3}x = 2 \), then \( x = 3^{2} = 9 \), we solve the problem using the exponential relationship inherent in logarithmic functions.
Graph Analysis
Graph analysis is an essential tool for visually understanding the behavior of functions and their interactions. When analyzing graphs, you can determine key features like intercepts, asymptotes, and points of intersection.

In this exercise, the goal was to approximate the intersection point of the given functions \( f(x) = \log_{3}x \) and \( g(x) = 2 \). By plotting the graphs, you can observe their behaviors. The graph of \( f(x) \) is a curve that increases gradually, while the graph of \( g(x) = 2 \) is a horizontal line.

By visually inspecting these graphs, one can approximate where they intersect, and in this case, it was near \( x = 9 \). This approximation is crucial as it provides an initial guess that can be verified and refined algebraically. Using graph analysis to make such approximations can save time and guide you toward the right solution path.
Solving Equations
Solving equations is a crucial skill, especially when you're finding the intersection of functions. In this task, you solved \( f(x) = g(x) \) algebraically to confirm the graphical approximation.

To solve this, set \( \log_{3}x = 2 \). This equation asks: "What number, when raised to the power of 2 as a base of 3, equals \( x \)?" Converting the logarithmic equation to an exponential form gives \( x = 3^{2} \), simplifying the task to simple arithmetic.

This solution confirms that \( x = 9 \), matching our earlier approximation from graph analysis and providing a precise answer. Algebraic solutions are critical because they provide exact results and validate approximations made from graph analysis, ensuring accuracy in mathematical problem-solving.

By understanding how to manipulate and solve equations, particularly those involving logarithmic functions, you'll gain a stronger foundation in tackling more complex mathematical challenges efficiently.

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