Simplify Exponential Expressions: A Step-by-Step Guide

by Kenji Nakamura 55 views

Hey guys! Let's dive into the world of exponents and simplify the expression 24β‹…2βˆ’223\frac{2^4 \cdot 2^{-2}}{2^3}. Don't worry, it might look intimidating at first, but we'll break it down step by step. Our goal is to write the answer without using exponents, so we'll need to understand how to manipulate these little superscript numbers.

To simplify expressions involving exponents, we need to recall the basic rules. The first key rule we'll use is the product of powers rule, which states that when you multiply powers with the same base, you add the exponents. Mathematically, this is expressed as amβ‹…an=am+na^m \cdot a^n = a^{m+n}. This rule is crucial for simplifying the numerator of our expression, where we have 24β‹…2βˆ’22^4 \cdot 2^{-2}. By applying the product of powers rule, we can combine these terms into a single power of 2. The second rule we will employ is the quotient of powers rule. This rule states that when dividing powers with the same base, you subtract the exponents. The mathematical representation of this rule is aman=amβˆ’n\frac{a^m}{a^n} = a^{m-n}. This rule will be essential for simplifying the entire expression once we've dealt with the numerator. Lastly, we will use the rule for negative exponents, which states that aβˆ’n=1ana^{-n} = \frac{1}{a^n}. This rule allows us to convert negative exponents into positive exponents by taking the reciprocal of the base raised to the positive exponent. Understanding and applying these exponent rules is the key to simplifying complex expressions effectively. In our case, we have a combination of multiplication and division involving exponents with the same base, so we'll strategically apply these rules to reduce the expression to its simplest form, a single number without any exponents. By mastering these exponent rules, you'll be able to tackle a wide range of mathematical problems and simplify expressions with confidence. So, let’s jump into the step-by-step solution and see how these rules work in practice.

Step 1: Simplify the Numerator

Let's start by focusing on the numerator: 24β‹…2βˆ’22^4 \cdot 2^{-2}. As we discussed, the product of powers rule tells us to add the exponents when multiplying powers with the same base. In this case, our base is 2, and our exponents are 4 and -2. So, we have:

24β‹…2βˆ’2=24+(βˆ’2)=24βˆ’2=222^4 \cdot 2^{-2} = 2^{4 + (-2)} = 2^{4 - 2} = 2^2

So, the numerator simplifies to 222^2. This step is crucial because it reduces the complexity of the expression, making it easier to handle in the subsequent steps. By combining the terms in the numerator, we've effectively condensed two exponential terms into a single term, which simplifies the overall calculation. The product of powers rule is a fundamental concept in algebra and is used extensively in simplifying expressions involving exponents. Understanding and applying this rule correctly is essential for solving more complex problems. Remember, when you see terms with the same base being multiplied, your first instinct should be to add their exponents. This step not only simplifies the expression but also lays the groundwork for the next step, where we'll deal with the division part of the original expression. By breaking down the problem into smaller, manageable steps, we can systematically simplify even the most intimidating-looking expressions. The key is to identify the relevant exponent rules and apply them in the correct order to achieve the simplest form.

Step 2: Apply the Quotient of Powers Rule

Now that we've simplified the numerator, our expression looks like this:

2223\frac{2^2}{2^3}

Here, we'll use the quotient of powers rule, which states that when dividing powers with the same base, you subtract the exponents. The base is still 2, and our exponents are 2 (from the numerator) and 3 (from the denominator). So:

2223=22βˆ’3=2βˆ’1\frac{2^2}{2^3} = 2^{2 - 3} = 2^{-1}

Applying the quotient of powers rule has further simplified our expression. We've gone from a fraction involving exponents to a single term with a negative exponent. This is a significant step towards our goal of expressing the answer without exponents. The quotient of powers rule is another cornerstone of exponent manipulation, and it's essential for simplifying expressions that involve division. Remember, the key to applying this rule correctly is to ensure that the bases are the same. Once you've confirmed that, you can confidently subtract the exponent in the denominator from the exponent in the numerator. This step is not only about simplifying the expression but also about transforming it into a form that allows us to apply other rules, such as the negative exponent rule, which we'll use in the next step. By understanding and applying the quotient of powers rule, you can efficiently simplify expressions involving division and pave the way for further simplification. So, let's move on to the final step and eliminate that negative exponent!

Step 3: Eliminate the Negative Exponent

We're almost there! We have 2βˆ’12^{-1}. To get rid of the negative exponent, we use the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}. This means we take the reciprocal of the base raised to the positive exponent:

2βˆ’1=121=122^{-1} = \frac{1}{2^1} = \frac{1}{2}

And there we have it! We've successfully simplified the expression and written the answer without using exponents. The final answer is 12\frac{1}{2}. This final step is crucial because it directly addresses the problem's requirement to express the answer without exponents. The negative exponent rule is a powerful tool for transforming expressions into a more familiar and easily understandable form. By understanding that a negative exponent indicates a reciprocal, we can rewrite expressions and simplify them effectively. In this case, 2βˆ’12^{-1} simply means the reciprocal of 212^1, which is 12\frac{1}{2}. This rule is not only useful for simplifying expressions but also for solving equations and understanding mathematical concepts in various fields. Remember, when you encounter a negative exponent, think about taking the reciprocal to make the exponent positive. This will often lead to a simplified and more manageable expression. So, by applying the negative exponent rule, we've completed the simplification process and arrived at our final answer, a fraction without any exponents. Great job, guys!

Final Answer

So, the simplified form of 24β‹…2βˆ’223\frac{2^4 \cdot 2^{-2}}{2^3} without using exponents is:

12\frac{1}{2}

Congratulations! You've successfully simplified the expression by applying the rules of exponents. Remember, the key is to break down the problem into smaller, manageable steps and apply the appropriate rules along the way. Keep practicing, and you'll become a master of exponents in no time!

Now that we've walked through the solution step-by-step, it's time to put your knowledge to the test with some practice problems. Understanding the theory is important, but the real learning happens when you apply those concepts to solve problems on your own. Practice helps solidify your understanding, builds confidence, and prepares you for more complex challenges in the future. Exponent rules are fundamental in algebra and calculus, so mastering them is crucial for your mathematical journey. These problems will cover a range of scenarios, including those involving product of powers, quotient of powers, and negative exponents. By working through these examples, you'll gain a deeper understanding of how each rule works and how to apply them in different contexts. Don't be afraid to make mistakes – they are a natural part of the learning process. The important thing is to learn from them and keep practicing. So, grab a pen and paper, and let's dive into some exciting practice problems to boost your exponent skills! Remember, consistency and dedication are key to mastering any mathematical concept.

Problem 1: Simplify 35β‹…3βˆ’232\frac{3^5 \cdot 3^{-2}}{3^2}

Problem 2: Simplify 5355\frac{5^3}{5^5}

Problem 3: Simplify 42β‹…4βˆ’34^2 \cdot 4^{-3}

Try these problems on your own, and remember the rules we discussed earlier. The product of powers rule, the quotient of powers rule, and the negative exponent rule are your best friends here. Don't hesitate to revisit the steps we took in the original problem if you get stuck. Remember, the goal is not just to find the answer but also to understand the process behind it. Each problem is designed to reinforce your understanding of a particular rule or a combination of rules. By working through these problems, you'll develop a strong foundation in exponent manipulation, which will serve you well in your future mathematical endeavors. So, take your time, be patient, and enjoy the process of solving these problems. The more you practice, the more confident and proficient you'll become in working with exponents. Happy solving!

To truly master exponents, it's beneficial to explore additional properties and concepts beyond the basic rules. Understanding these concepts will give you a more complete picture of how exponents work and enable you to tackle a wider range of problems. One important concept is the power of a power rule, which states that (am)n=amβ‹…n(a^m)^n = a^{m \cdot n}. This rule is particularly useful when dealing with expressions where an exponent is raised to another exponent. Another crucial property is the power of a product rule, which states that (ab)n=anbn(ab)^n = a^n b^n. This rule allows you to distribute an exponent over a product. Similarly, the power of a quotient rule states that (ab)n=anbn(\frac{a}{b})^n = \frac{a^n}{b^n}, which allows you to distribute an exponent over a quotient. Additionally, understanding fractional exponents and their relationship to radicals is essential. For example, a1na^{\frac{1}{n}} is equivalent to the nth root of a, denoted as an\sqrt[n]{a}. This connection between exponents and radicals opens up a whole new world of mathematical possibilities. Exploring these advanced exponent properties will not only enhance your problem-solving skills but also deepen your understanding of mathematical relationships. So, take some time to delve into these concepts and expand your knowledge of exponents. The more you explore, the more you'll appreciate the power and versatility of exponents in mathematics.

By mastering these rules and practicing regularly, you'll be able to tackle even the most complex exponent problems with ease. Keep up the great work!