Solving 4ⁿ × 8ⁿ = 2¹⁰ A Step-by-Step Guide

by Henrik Larsen 43 views

Are you grappling with exponential equations? Do problems like 4ⁿ × 8ⁿ = 2¹⁰ seem daunting? Don't worry, you're not alone! Exponential equations might appear tricky at first, but with a systematic approach and a solid understanding of the underlying principles, you can conquer them. In this comprehensive guide, we'll break down the steps to solve the equation 4ⁿ × 8ⁿ = 2¹⁰, and by the end of this article, you'll not only have the solution but also a firm grasp of the techniques involved. Let's dive in and unravel the mysteries of exponential equations!

Understanding Exponential Equations

Before we jump into solving the equation, let's briefly discuss what exponential equations are. Exponential equations are equations in which the variable appears in the exponent. They are a fundamental part of algebra and calculus, and they pop up in various real-world applications, such as calculating compound interest, modeling population growth, and understanding radioactive decay. Understanding the properties of exponents is crucial for solving these equations. Key properties include the product of powers rule (aᵐ × aⁿ = aᵐ⁺ⁿ), the power of a power rule ((aᵐ)ⁿ = aᵐⁿ), and the quotient of powers rule (aᵐ / aⁿ = aᵐ⁻ⁿ). These rules allow us to manipulate exponential expressions and simplify equations, making them easier to solve. Recognizing these patterns and applying these rules correctly is half the battle in tackling exponential equations. In this guide, we will leverage these properties to break down the equation 4ⁿ × 8ⁿ = 2¹⁰ and solve for the unknown variable, n. Remember, practice makes perfect, so as we go through the steps, try to apply these principles to other similar problems. Soon, you'll find yourself solving exponential equations with ease!

Step 1: Express All Terms with the Same Base

The first crucial step in solving the equation 4ⁿ × 8ⁿ = 2¹⁰ is to express all the terms with the same base. This simplifies the equation and allows us to compare exponents directly. In this case, we can express 4 and 8 as powers of 2. Remember, 4 is 2², and 8 is 2³. So, let’s rewrite the equation using 2 as the base: 4ⁿ × 8ⁿ = (2²)ⁿ × (2³)ⁿ = 2¹⁰. Now we have the equation in a form where all terms have the same base. This transformation is vital because it allows us to apply the properties of exponents more effectively. By expressing all terms with a common base, we can combine and simplify the exponents, ultimately leading to a solvable equation. This step highlights the importance of recognizing the relationships between numbers and their prime factorizations. The ability to quickly identify common bases is a valuable skill in solving exponential equations. Keep in mind that choosing the simplest common base often makes the problem easier to handle. As you practice, you'll become more adept at spotting these relationships and choosing the most efficient base for simplification. This foundational step is the key to unlocking the solution to many exponential equation problems.

Step 2: Apply the Power of a Power Rule

Now that we have expressed all terms with the same base, we need to apply the power of a power rule. This rule states that (aᵐ)ⁿ = aᵐⁿ. Applying this rule to our equation, (2²)ⁿ × (2³)ⁿ = 2¹⁰, we get 2²ⁿ × 2³ⁿ = 2¹⁰. By using the power of a power rule, we have further simplified the equation, making it easier to manipulate and solve. This rule is a cornerstone in working with exponents, and mastering its application is essential for solving exponential equations. It allows us to deal with nested exponents by multiplying them together, thereby reducing the complexity of the expression. In the context of our equation, applying this rule allows us to transform the original equation into a form where we can easily combine the terms with the same base. Understanding and applying the power of a power rule correctly is a fundamental skill for anyone tackling exponential equations. It is one of the key techniques that allows us to move from complex expressions to simpler, more manageable forms. Make sure to practice this rule with various examples to solidify your understanding and become proficient in its application.

Step 3: Apply the Product of Powers Rule

The next step is to apply the product of powers rule, which states that aᵐ × aⁿ = aᵐ⁺ⁿ. In our equation, 2²ⁿ × 2³ⁿ = 2¹⁰, we have two exponential terms with the same base being multiplied. Applying the product of powers rule, we add the exponents: 2²ⁿ⁺³ⁿ = 2¹⁰. This simplifies the equation to 2⁵ⁿ = 2¹⁰. The product of powers rule is a fundamental principle in algebra that allows us to combine exponential terms when they share the same base. By adding the exponents, we are essentially condensing the expression into a more manageable form. This rule is not only applicable to solving exponential equations but also to simplifying algebraic expressions in general. It is a core concept that forms the foundation for many algebraic manipulations. In the context of our problem, this step brings us closer to isolating the variable n. By combining the exponents, we have reduced the equation to a form where we can directly compare the exponents on both sides. Mastering the product of powers rule is crucial for anyone working with exponents and exponential equations. It is a versatile tool that simplifies expressions and makes problem-solving much more efficient.

Step 4: Equate the Exponents

Now that we have the equation 2⁵ⁿ = 2¹⁰, the bases are the same on both sides. This allows us to equate the exponents. If aˣ = aʸ, then x = y. Therefore, in our equation, we can say that 5n = 10. This step is a crucial point in solving exponential equations because it transforms the problem from dealing with exponents to a simple algebraic equation. Equating the exponents is only valid when the bases are the same. This principle allows us to bypass the exponential form and focus on solving for the variable in a linear equation. This step demonstrates the power of manipulating the equation to a form where we can apply direct comparison. By equating the exponents, we have effectively eliminated the exponential aspect of the problem, making it straightforward to solve for n. Understanding when and how to equate exponents is a key skill in solving exponential equations. It is a technique that turns complex problems into manageable steps. Make sure you recognize when this step is applicable, as it is a powerful tool in your problem-solving arsenal.

Step 5: Solve for the Variable

We now have the simple algebraic equation 5n = 10. To solve for n, we divide both sides of the equation by 5: 5n / 5 = 10 / 5, which gives us n = 2. This is the solution to our exponential equation. Solving for the variable is the final step in the process, and it often involves basic algebraic manipulations. In this case, dividing both sides of the equation by the coefficient of the variable isolates the variable and provides the solution. This step underscores the importance of a solid foundation in basic algebra. The ability to quickly and accurately solve simple equations is crucial for tackling more complex problems. In the context of exponential equations, solving for the variable allows us to find the value that satisfies the original equation. This final step brings closure to the problem-solving process and provides a concrete answer. Make sure you are comfortable with basic algebraic techniques, as they are essential for solving a wide range of mathematical problems, including exponential equations.

Final Answer: n = 2

So, the solution to the exponential equation 4ⁿ × 8ⁿ = 2¹⁰ is n = 2. We've successfully navigated through the steps, from expressing terms with the same base to equating exponents and finally solving for the variable. Remember, practice is key to mastering these techniques. Work through similar problems, and you'll soon find yourself confidently solving exponential equations. The journey through this equation highlights the importance of understanding and applying the properties of exponents. By breaking down the problem into manageable steps, we were able to transform a seemingly complex equation into a straightforward algebraic problem. This approach is applicable to a wide range of exponential equations, and with practice, you'll be able to tackle them with ease. Keep exploring and keep solving, and you'll unlock the power of exponential equations!

Practice Problems

To solidify your understanding, try solving these similar exponential equations:

  1. 9ˣ × 27ˣ = 3¹⁵
  2. 2^(x+1) = 8
  3. 5^(2x) = 125

These practice problems will give you the opportunity to apply the steps we've discussed in this guide. Remember to express all terms with the same base, apply the power of a power rule and the product of powers rule, equate the exponents, and solve for the variable. Working through these problems will not only reinforce your understanding but also build your confidence in solving exponential equations. Each problem presents a unique opportunity to practice the techniques and strategies we've covered. Don't hesitate to review the steps outlined in this guide if you get stuck. The goal is not just to find the answers but to understand the process and the underlying principles. As you solve more problems, you'll develop a deeper intuition for exponential equations and become more adept at tackling them. So, grab a pen and paper, and let's put your newfound knowledge to the test!

By working through these examples and the problems provided, you'll not only master this specific equation but also gain a solid foundation for solving a wide range of exponential equations. Keep practicing, and you'll become an exponential equation whiz in no time!