Solving For N In Exponential Equation: A Step-by-Step Guide

by Andrew McMorgan 60 views

Hey math enthusiasts! Today, we're diving deep into the world of exponential equations. We're going to break down a specific problem step-by-step, making sure you understand not just the how, but also the why behind each move. So, if you've ever scratched your head trying to solve for a variable tucked away in an exponent, you're in the right place. Let's get started!

Understanding the Problem: 216^(n-2) / (1/36)^(3n) = 216

Okay, let's tackle this equation: 216^(n-2) / (1/36)^(3n) = 216. At first glance, it might seem a bit intimidating with all those exponents and fractions. But don't worry, we're going to break it down into manageable chunks. The key to solving exponential equations like this one is to express all terms with the same base. This allows us to equate the exponents and solve for our variable, 'n'. So, our main keyword here is solving for 'n', and we'll be doing that by manipulating the equation to have a common base. We'll explore different methods and explain why each step is crucial. Remember, the goal is not just to find the answer but to understand the process. This understanding will help you tackle similar problems in the future with confidence. So, let's roll up our sleeves and dive into the exciting world of exponents! We'll start by identifying the common base we can use and then rewrite the equation accordingly. Stay tuned, because the next steps are going to make everything crystal clear!

Step 1: Expressing All Terms with a Common Base

Now, let's get to the core of the problem: expressing all terms with a common base. Looking at our equation, 216^(n-2) / (1/36)^(3n) = 216, we need to find a base that 216 and 1/36 can both be expressed as powers of. If you're familiar with powers of 6, you might already have an idea. That's right, both 216 and 36 are powers of 6! Specifically, 216 is 6 cubed (6^3), and 36 is 6 squared (6^2). This is a crucial step, guys, because finding the common base simplifies the entire equation. So, let's rewrite our terms: 216 can be written as 6^3, and 1/36 can be written as 6^(-2) (remember, a negative exponent means we're dealing with the reciprocal). Now, we'll substitute these expressions back into our original equation. This substitution is the key to unlocking the solution. By having a common base, we're setting the stage to equate the exponents, which is a much simpler task. So, let's replace 216 with 6^3 and 1/36 with 6^(-2) in our equation. This will give us a new form of the equation that's much easier to handle. This step highlights the power of recognizing patterns and using fundamental exponent rules. It's like finding the right key to unlock a door – once we have the common base, the rest of the solution unfolds more smoothly. Up next, we'll see how this substitution transforms our equation and brings us closer to solving for 'n'. Keep those thinking caps on!

Step 2: Substituting and Simplifying the Equation

Alright, with our common base of 6 identified, let's substitute these values back into the equation. Remember, our equation is 216^(n-2) / (1/36)^(3n) = 216. We've established that 216 = 6^3 and 1/36 = 6^(-2). So, let's plug those in! This gives us (63)(n-2) / (6(-2))(3n) = 6^3. See how things are starting to look simpler? Now, we're going to use a crucial exponent rule: (am)n = a^(mn). This rule tells us that when we raise a power to another power, we multiply the exponents. Applying this rule to our equation, we get 6^(3(n-2)) / 6^(-23n) = 6^3. Let's simplify those exponents: 3(n-2) becomes 3n - 6, and -2*3n becomes -6n. So our equation now looks like this: 6^(3n-6) / 6^(-6n) = 6^3. We're making great progress! The next step involves dealing with the division of exponents with the same base. This is where another exponent rule comes into play. Remember, when dividing exponents with the same base, we subtract the exponents. So, stay with us as we move on to the next step and tackle that division!

Step 3: Applying the Quotient Rule of Exponents

Okay, guys, we're on a roll! Our equation currently looks like this: 6^(3n-6) / 6^(-6n) = 6^3. Now it's time to use the quotient rule of exponents. This rule states that a^m / a^n = a^(m-n). In simpler terms, when you divide powers with the same base, you subtract the exponents. Applying this rule to our equation, we get 6^((3n-6) - (-6n)) = 6^3. Notice how we're subtracting the entire exponent (-6n). It's super important to pay attention to those signs! Now, let's simplify the exponent on the left side. We have (3n - 6) - (-6n), which is the same as 3n - 6 + 6n. Combining like terms, we get 9n - 6. So our equation now becomes 6^(9n-6) = 6^3. We're getting so close to solving for 'n'! We've managed to get both sides of the equation expressed as a power of 6. This means we can now equate the exponents. In the next step, we'll do just that and finally isolate 'n'. Stick with it, we're almost there!

Step 4: Equating the Exponents and Solving for n

Here's where the magic happens! Our equation is now in the form 6^(9n-6) = 6^3. Since the bases are the same, we can confidently equate the exponents. This means we can say 9n - 6 = 3. See how we've transformed a complicated exponential equation into a simple linear equation? This is the power of using the rules of exponents! Now, let's solve for 'n'. First, we'll add 6 to both sides of the equation: 9n - 6 + 6 = 3 + 6, which simplifies to 9n = 9. Next, we'll divide both sides by 9: 9n / 9 = 9 / 9, which gives us n = 1. And there we have it! We've successfully solved for 'n'. But before we celebrate, it's always a good idea to double-check our answer. In the next step, we'll plug n = 1 back into the original equation to make sure it holds true. This is a crucial step to ensure we haven't made any errors along the way. So, let's verify our solution and put our minds at ease!

Step 5: Verifying the Solution

Alright, let's put our solution to the test! We found that n = 1, and we want to make sure this value satisfies our original equation: 216^(n-2) / (1/36)^(3n) = 216. Let's substitute n = 1 into the equation: 216^(1-2) / (1/36)^(3*1) = 216. Now, let's simplify: 216^(-1) / (1/36)^3 = 216. Remember that a negative exponent means we take the reciprocal, so 216^(-1) is 1/216. And (1/36)^3 is 1/36 * 1/36 * 1/36, which equals 1/46656. Our equation now looks like this: (1/216) / (1/46656) = 216. Dividing by a fraction is the same as multiplying by its reciprocal, so we have (1/216) * (46656/1) = 216. Now, let's simplify: 46656 / 216 = 216. And guess what? 46656 divided by 216 is indeed 216! So, our equation holds true. This confirms that our solution, n = 1, is correct. We've successfully navigated the world of exponents and solved for 'n'. Give yourselves a pat on the back, guys! You've not only found the answer but also understood the process behind it. Remember, practice makes perfect, so keep exploring and tackling those math challenges. You've got this!

Conclusion: Mastering Exponential Equations

So, there you have it, guys! We've successfully solved the equation 216^(n-2) / (1/36)^(3n) = 216 and found that n = 1. We walked through each step, from identifying the common base to verifying our solution. We used key exponent rules like (am)n = a^(m*n) and a^m / a^n = a^(m-n). And most importantly, we emphasized the why behind each step. Remember, mastering exponential equations is all about understanding the underlying principles and practicing consistently. Don't be afraid to break down complex problems into smaller, manageable steps. And always double-check your work! We hope this guide has been helpful and has given you the confidence to tackle similar problems. Keep exploring the fascinating world of mathematics, and remember, every problem is an opportunity to learn and grow. Until next time, keep those numbers crunching!