/*! 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 54 Use a graphing utility to solve ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Use a graphing utility to solve each equation for \(x.\) $$7=4^{x}$$

Short Answer

Expert verified
Using a graphing utility, \(x\) is found to be approximately 1.404.

Step by step solution

01

Understand the Exponential Equation

The given equation is \(7=4^{x}\). It is an exponential equation since the variable \(x\) is in the exponent.
02

Set up the Equation in the Graphing Utility

Input the given equation into the graphing utility. Do this by plotting two separate equations: \(y=7\) and \(y=4^{x}\). The graphing utility should then draw two lines representing these equations.
03

Determining the Solution

The solution to the equation will be the \(x\)-value at the point where the two lines intersect. This is because at the point of intersection, the \(y\)-values of the two functions are equal, meaning the two sides of the equation are equal. The graphing utility can be used to precisely calculate the intersection point and thus solve the equation.

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Key Concepts

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

Graphing Utilities
Graphing utilities are powerful tools that help us visualize mathematical equations by plotting them on a coordinate plane. Imagine them as advanced calculators that can show you the entire shape of an equation at once. They are especially useful for solving equations that are otherwise tricky to handle, like exponential equations where the variable is in an exponent. When you use a graphing utility, you start by entering each side of the equation as a separate function. For instance, for the equation \(7 = 4^x\), you would input two functions: \(y = 7\) and \(y = 4^x\). The utility plots these on a graph, allowing you to see where they might intersect.
  • Graphing utilities can handle various types of equations, from linear to more complex curves.
  • They often have features that allow zooming and adjusting the view to better find intersection points.
  • Some also provide numerical estimations for roots, intersections, and other critical features of the graph.
By equipping students with the visual representation of an equation, graphing utilities make it easier to comprehend and solve complex equations.
Exponential Functions
Exponential functions are a unique class of mathematical functions with the variable found in the exponent. They often have the form \(f(x) = a \cdot b^x\), where \(b\) is a positive constant base. These functions grow quickly due to the repeated multiplication as the variable \(x\) increases, which can result in steep curves on a graph. In our equation, \(4^x\) is an exponential function where the base is 4.
  • Exponential functions differ significantly from linear functions because they do not form straight lines. Instead, they curve upwards steeply as \(x\) increases.
  • This makes them powerful models for phenomena such as population growth, radioactive decay, and interest calculations in finance.
  • The key feature of exponential growth is that the rate of growth is proportional to the current amount. This results in very rapid change as the function value rises.
Understanding their nature is crucial when graphing because it helps anticipate where they might meet other functions on a coordinate plane.
Intersection Points
Intersection points on a graph offer the solution to systems of equations, especially when dealing with two functions like in our equation \(7 = 4^x\). They represent the specific \(x\) and \(y\) coordinates where two graphs meet or cross each other.When graphing the functions \(y = 7\) and \(y = 4^x\), the intersection point's \(x\)-coordinate is actually the solution to the original equation. At this spot, both functions share the same \(y\)-value, fulfilling the equation's requirement of both sides being equal.
  • Finding the intersection involves visually identifying where the lines or curves meet on the graph.
  • Graphing utilities streamline this process by allowing users to accurately calculate the intersection coordinates.
  • Understanding intersections also aids in comprehending the behaviors of different functions relative to one another.
By solving for the intersection, students can effectively resolve equations and gain deeper insights into mathematical relationships.

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Most popular questions from this chapter

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