Finding The Value Of (f(a-2) - F(a))/4 Given F_n = N^2 - 2

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In the realm of mathematics, functions often present intriguing challenges, demanding a blend of algebraic manipulation and insightful understanding. Today, we embark on a journey to unravel the mystery behind a specific function, f_n = n^2 - 2, and determine the value of the expression (f(a-2) - f(a))/4. This exploration will not only test our algebraic prowess but also deepen our appreciation for the elegance of mathematical relationships. This article aims to provide a comprehensive and accessible guide to solving this problem, ensuring that readers of all backgrounds can grasp the underlying concepts and techniques. Whether you're a student grappling with function evaluations or a seasoned mathematician seeking a refresher, this article has something to offer. We will break down the problem into manageable steps, providing clear explanations and insightful commentary along the way. So, let's delve into the world of functions and discover the solution to this intriguing puzzle.

Understanding the Function and the Problem

Before we dive into the calculations, let's take a moment to truly understand the function and the problem at hand. We are given the function f_n = n^2 - 2, which tells us that for any input n, the function squares the input and then subtracts 2. Our goal is to find the value of the expression (f(a-2) - f(a))/4. This expression involves evaluating the function at two different inputs, a-2 and a, subtracting the results, and then dividing the difference by 4. The key to solving this problem lies in carefully substituting the inputs into the function and then simplifying the resulting expression. It's like deciphering a code, where each step unveils a piece of the puzzle, ultimately leading us to the final answer. This initial understanding is crucial because it sets the stage for the subsequent algebraic manipulations. Without a clear grasp of the problem, we risk getting lost in the calculations and missing the underlying logic. So, let's proceed with confidence, knowing that we have a solid foundation to build upon.

Evaluating f(a-2)

The first step in solving the problem is to evaluate f(a-2). To do this, we substitute (a-2) for n in the function f_n = n^2 - 2. This gives us f(a-2) = (a-2)^2 - 2. Now, we need to expand the square (a-2)^2. Recall that (a-2)^2 = (a-2)(a-2). Using the distributive property (or the FOIL method), we get (a-2)(a-2) = a^2 - 2a - 2a + 4 = a^2 - 4a + 4. Therefore, f(a-2) = a^2 - 4a + 4 - 2. Simplifying this expression, we get f(a-2) = a^2 - 4a + 2. This is a crucial intermediate result, as it represents the value of the function at the input a-2. The process of substitution and simplification is fundamental in evaluating functions, and mastering this skill is essential for tackling more complex problems. By carefully expanding the square and combining like terms, we have successfully found the expression for f(a-2), which will be used in the next step of our solution.

Evaluating f(a)

Next, we need to evaluate f(a). This is a more straightforward step, as we simply substitute a for n in the function f_n = n^2 - 2. This gives us f(a) = a^2 - 2. This result is relatively simple, but it's equally important as f(a-2) in our quest to find the value of the given expression. Evaluating functions at specific inputs is a cornerstone of mathematical analysis, and this step reinforces our understanding of this fundamental concept. With both f(a-2) and f(a) now determined, we are well-positioned to move on to the next stage of the problem, which involves subtracting these two values. The simplicity of this step should not be overlooked, as it contributes significantly to the overall solution process. It's a reminder that even the most complex problems can often be broken down into smaller, more manageable parts.

Calculating f(a-2) - f(a)

Now that we have f(a-2) = a^2 - 4a + 2 and f(a) = a^2 - 2, we can calculate the difference f(a-2) - f(a). This involves subtracting the expression for f(a) from the expression for f(a-2). So, f(a-2) - f(a) = (a^2 - 4a + 2) - (a^2 - 2). To simplify this expression, we need to distribute the negative sign in front of the second parentheses: (a^2 - 4a + 2) - (a^2 - 2) = a^2 - 4a + 2 - a^2 + 2. Now, we can combine like terms: a^2 - a^2 - 4a + 2 + 2 = -4a + 4. Therefore, f(a-2) - f(a) = -4a + 4. This result is a key step in solving the problem, as it represents the numerator of the expression we are trying to find. The process of subtracting polynomials and simplifying the result is a common algebraic technique, and this step provides a practical application of this skill. By carefully tracking the signs and combining like terms, we have successfully calculated the difference between f(a-2) and f(a), bringing us closer to the final solution.

Finding (f(a-2) - f(a))/4

Finally, we can find the value of the expression (f(a-2) - f(a))/4. We have already calculated that f(a-2) - f(a) = -4a + 4. So, to find (f(a-2) - f(a))/4, we simply divide the expression -4a + 4 by 4. This gives us (-4a + 4)/4. We can simplify this expression by factoring out a 4 from the numerator: (-4a + 4)/4 = 4(-a + 1)/4. Now, we can cancel the 4 in the numerator and the denominator, which leaves us with -a + 1 or 1 - a. Therefore, the value of the expression (f(a-2) - f(a))/4 is 1 - a. This is the final answer to our problem. We have successfully navigated through the steps of evaluating the function, substituting inputs, simplifying expressions, and ultimately arriving at the solution. This journey has demonstrated the power of algebraic manipulation and the importance of careful attention to detail. The result, 1 - a, is a concise and elegant expression that encapsulates the relationship between the function and the given expression.

Conclusion

In conclusion, we have successfully found that if f_n = n^2 - 2, then (f(a-2) - f(a))/4 = 1 - a. This problem has provided a valuable exercise in function evaluation, algebraic manipulation, and simplification. By breaking down the problem into smaller, more manageable steps, we were able to navigate through the calculations with clarity and precision. The solution highlights the beauty and elegance of mathematical relationships, where seemingly complex expressions can be simplified to reveal underlying patterns and connections. This exploration has not only enhanced our problem-solving skills but also deepened our appreciation for the power and versatility of mathematics. The journey from the initial problem statement to the final solution has been a testament to the importance of perseverance, attention to detail, and a solid understanding of fundamental mathematical concepts. We hope this article has provided a clear and comprehensive guide to solving this problem, and that it has inspired readers to continue exploring the fascinating world of mathematics.