Evaluating Logarithmic Expression Log(sqrt(x^5 * Y^3)) Without Calculator

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Logarithmic expressions can appear daunting at first glance, but with a strong understanding of the fundamental logarithmic properties, they can be simplified and evaluated efficiently, even without the aid of a calculator. This article will guide you through the step-by-step process of evaluating the given logarithmic expression, logx5y3\log \sqrt{x^5 \cdot y^3}, using the provided logarithmic values of xx, yy, 2, and 3. By applying these properties and values strategically, we can break down the complex expression into simpler components, ultimately leading to the final solution. This exploration will not only enhance your problem-solving skills but also solidify your grasp of logarithmic concepts. Our main goal is to simplify and calculate the value of the given logarithmic expression by utilizing the properties of logarithms and the provided approximations. To effectively tackle this problem, we'll need to understand and apply the key logarithmic properties, such as the power rule, the product rule, and the definition of logarithms. With the understanding of these properties, we will be able to break down complex expressions into simpler, manageable parts, paving the way for an accurate calculation. By the end of this detailed explanation, you'll not only find the solution to the expression but also strengthen your understanding of how to manipulate and evaluate logarithmic expressions in various contexts. This fundamental skill is crucial for anyone delving deeper into mathematics, particularly in areas like calculus and complex analysis, where logarithms frequently arise.

Understanding Logarithmic Properties

Before we dive into the evaluation, let's refresh our understanding of the essential logarithmic properties that will play a crucial role in simplifying the expression. The key properties include the power rule, the product rule, and the definition of logarithms. The power rule states that logb(ac)=clogb(a)\log_b(a^c) = c \cdot \log_b(a), which allows us to move exponents out of the logarithm. The product rule states that logb(ac)=logb(a)+logb(c)\log_b(a \cdot c) = \log_b(a) + \log_b(c), enabling us to separate the logarithm of a product into a sum of logarithms. Understanding these rules is crucial because they provide us with the tools to manipulate and simplify logarithmic expressions effectively. For example, the power rule lets us handle exponents within logarithms, while the product rule allows us to break down complex multiplications into simpler additions. The understanding of the definition of a logarithm itself is paramount. If logb(a)=x\log_b(a) = x, then bx=ab^x = a. This definition helps us understand the inverse relationship between logarithms and exponentiation, which is useful in converting between logarithmic and exponential forms. These rules, when combined, give us a powerful toolkit for solving logarithmic problems. Without a solid grasp of these properties, simplifying and evaluating logarithmic expressions becomes significantly more difficult. Therefore, mastering these foundational concepts is not just about solving this specific problem but also about building a strong base for future mathematical endeavors. We will use these principles extensively in the following steps to break down the given expression and find its value. Each property will be applied strategically to transform the original expression into a form that is easier to compute using the given values of logx\log x, logy\log y, log2\log 2, and log3\log 3.

Step-by-Step Evaluation

Let's begin the step-by-step evaluation of the expression logx5y3\log \sqrt{x^5 \cdot y^3}. The first step involves rewriting the square root as an exponent. Recall that the square root of a number can be expressed as raising that number to the power of 1/2. So, we can rewrite the expression as: log(x5y3)12\log (x^5 \cdot y^3)^{\frac{1}{2}}. This initial transformation is crucial because it sets the stage for applying the power rule of logarithms. By expressing the square root as an exponent, we can now use the power rule to bring the exponent outside the logarithm, simplifying the expression further. This approach is a common technique in dealing with radical expressions within logarithms and allows us to manipulate the expression in a more manageable way. The next step involves using the power rule of logarithms. The power rule states that logb(ac)=clogb(a)\log_b(a^c) = c \cdot \log_b(a). Applying this rule to our expression, we get: 12log(x5y3)\frac{1}{2} \cdot \log (x^5 \cdot y^3). This step is pivotal as it effectively removes the fractional exponent, making the expression inside the logarithm more accessible. Now, we can focus on the product within the logarithm. The power rule has allowed us to shift the complexity from dealing with an exponent outside the logarithm to focusing on the multiplication inside. This is a significant simplification that brings us closer to our final evaluation. Now, we apply the product rule of logarithms. The product rule states that logb(ac)=logb(a)+logb(c)\log_b(a \cdot c) = \log_b(a) + \log_b(c). Applying this rule, we can separate the product inside the logarithm into a sum of logarithms: 12(logx5+logy3)\frac{1}{2} \cdot (\log x^5 + \log y^3). This step is a crucial transformation as it breaks down the complex product into simpler additive components. By separating the terms, we can now deal with each logarithmic term individually, making the problem more manageable. This approach is a fundamental technique in logarithmic simplification, and it paves the way for using other logarithmic properties. We apply the power rule again to each term inside the parentheses. This gives us: 12(5logx+3logy)\frac{1}{2} \cdot (5 \log x + 3 \log y). This application of the power rule is the key to utilizing the given values of logx\log x and logy\log y. By bringing the exponents down as coefficients, we've set up the expression so that we can substitute the known values and compute the result. At this point, we have successfully transformed the original expression into a form that directly relates to the given logarithmic values. All the logarithmic operations are now reduced to simple multiplication and addition, which makes the calculation straightforward. Finally, substitute the given values logx=2\log x = 2 and logy=3\log y = 3: 12(52+33)\frac{1}{2} \cdot (5 \cdot 2 + 3 \cdot 3). This substitution is the culmination of our simplification process. We've successfully reduced the original complex expression into a simple arithmetic calculation. Now, it's just a matter of performing the multiplication and addition to find the final answer. This step highlights the power of logarithmic properties in simplifying expressions and making them easier to evaluate. We've turned a potentially challenging logarithmic problem into a basic arithmetic problem by strategically applying the logarithmic rules. Now, we perform the arithmetic: 12(10+9)=1219=9.5\frac{1}{2} \cdot (10 + 9) = \frac{1}{2} \cdot 19 = 9.5. This final calculation provides the solution to the problem. By following the step-by-step simplification and evaluation process, we have successfully found the value of the logarithmic expression without using a calculator. The answer is 9.5. This result demonstrates the effectiveness of using logarithmic properties to simplify complex expressions. Each step in the process, from converting the square root to an exponent to applying the power and product rules, was crucial in transforming the original expression into a manageable form. This detailed walkthrough not only provides the solution but also reinforces the importance of understanding and applying logarithmic properties in problem-solving.

Final Result

Therefore, the final result of evaluating the expression logx5y3\log \sqrt{x^5 \cdot y^3}, given logx=2\log x=2 and logy=3\log y=3, is 9.5. This result showcases the power and efficiency of using logarithmic properties to simplify complex expressions. The ability to manipulate logarithmic expressions using these rules is a valuable skill in mathematics, allowing for the simplification and evaluation of problems that might otherwise seem insurmountable. Understanding these properties not only aids in solving specific problems but also builds a solid foundation for more advanced mathematical concepts. By mastering these skills, one can confidently approach and solve a wide range of logarithmic problems, making complex calculations more accessible and manageable.

logx5y3=9.5\log \sqrt{x^5 \cdot y^3} = 9.5