Simplifying 3 * 2 * (9^(2/3)) A Step-by-Step Guide

by Brainly ES FTUNILA 51 views
Iklan Headers

Hey there, math enthusiasts! Ever stumbled upon an equation that looks like a jumbled mess of numbers and symbols? Don't worry, we've all been there. Today, we're going to tackle one such equation: 3 * 2 * (9^(2/3)). It might seem intimidating at first glance, but trust me, with a little bit of algebraic wizardry, we can break it down and solve it together.

Decoding the Exponent: What Does 9^(2/3) Really Mean?

Before we dive into the calculations, let's first understand what that fractional exponent (2/3) is telling us. Remember, exponents aren't just about repeated multiplication; they can also represent roots. A fractional exponent like 2/3 combines both a power and a root. The denominator (3 in this case) indicates the type of root we're dealing with – a cube root. The numerator (2) tells us the power to which we raise the base (9) after taking the root.

So, 9^(2/3) can be interpreted as "the cube root of 9 squared" or, equivalently, "9 squared, then take the cube root." Think of it as a two-step process: first, we square the base, and then we find the cube root of the result. This understanding is crucial for simplifying the expression and revealing its true value. We'll walk through both interpretations to solidify this concept. By grasping the meaning behind fractional exponents, you'll be able to confidently tackle similar problems in the future. It's like having a secret decoder ring for mathematical expressions!

The Cube Root Connection: Why is it so Important?

The cube root is the key player in this equation, guys. It's the magic that unlocks the simplified answer. Think of it this way: finding the cube root of a number is like asking, "What number, when multiplied by itself three times, gives me this original number?" For example, the cube root of 8 is 2, because 2 * 2 * 2 = 8. Similarly, the cube root of 27 is 3, because 3 * 3 * 3 = 27. This concept is fundamental to understanding how fractional exponents work and how they allow us to simplify complex expressions. In our case, we need to find the cube root of 9 squared, which might seem tricky at first. But don't worry, we'll break it down step by step. Understanding cube roots not only helps us solve this specific problem but also opens the door to tackling a wide range of mathematical challenges involving radicals and exponents. So, let's embrace the power of cube roots and see how they simplify our equation!

Method 1: Squaring First, Then Finding the Cube Root

Let's tackle the equation using our first approach: squaring the base (9) and then finding the cube root. This method helps visualize the order of operations and reinforces the concept of fractional exponents. First, we calculate 9 squared, which is 9 * 9 = 81. So now our expression inside the parentheses looks like the cube root of 81, or ∛81. This is where things get interesting! We need to figure out what number, when multiplied by itself three times, equals 81. Now, 81 isn't a perfect cube (like 8 or 27), so we need to get a bit creative. We can start by factoring 81 to see if we can find any perfect cube factors hiding within it. Factoring 81, we get 81 = 3 * 3 * 3 * 3 = 3^4. This is where the magic happens: we can rewrite ∛81 as ∛(3^3 * 3). Remember, the cube root of a product is the product of the cube roots. So, ∛(3^3 * 3) becomes ∛(3^3) * ∛3. The cube root of 3^3 is simply 3, leaving us with 3 * ∛3. This simplified form of ∛81 is much easier to work with, and it showcases the power of factoring and understanding cube roots. By breaking down the problem into smaller steps, we've successfully navigated a seemingly complex calculation. This method highlights the importance of understanding the properties of exponents and roots, allowing us to manipulate expressions and find their simplest forms.

Method 2: Finding the Cube Root First, Then Squaring

Now, let's explore the second approach to solving 9^(2/3): finding the cube root of 9 first, and then squaring the result. This method offers a slightly different perspective and can be particularly useful when dealing with larger exponents or bases. Remember, the order of operations can sometimes be rearranged to make calculations easier. In this case, taking the cube root before squaring might seem less intuitive, but it can lead to a more streamlined solution. So, we start by finding the cube root of 9, which we can write as ∛9. Unlike perfect cubes like 8 or 27, 9 doesn't have a whole number cube root. It's an irrational number, meaning its decimal representation goes on forever without repeating. However, we don't need to find the exact decimal value of ∛9 just yet. We can leave it in its radical form for now and proceed to the next step: squaring it. Squaring ∛9 means multiplying it by itself: (∛9) * (∛9). This is where the properties of radicals come into play. When multiplying radicals with the same index (in this case, the cube root), we can multiply the radicands (the numbers inside the radical). So, (∛9) * (∛9) = ∛(9 * 9) = ∛81. Notice that we've arrived back at the same point as in Method 1! This demonstrates the flexibility of fractional exponents and the different paths we can take to reach the solution. From here, we can follow the same steps as in Method 1 to simplify ∛81, factoring it as ∛(3^3 * 3) and arriving at the final simplified form of 3 * ∛3. By exploring this alternative approach, we've not only reinforced our understanding of fractional exponents but also gained valuable problem-solving skills. It's all about finding the method that clicks best for you and mastering the underlying principles.

Putting it All Together: Solving the Original Equation

Alright, guys, we've successfully decoded the mystery of 9^(2/3) using two different methods! Now it's time to bring it all together and solve the original equation: 3 * 2 * (9^(2/3)). We know from our previous calculations that 9^(2/3) simplifies to 3 * ∛3. So, we can substitute this value back into the original equation: 3 * 2 * (3 * ∛3). Now it's just a matter of simple multiplication. We can multiply the whole numbers together: 3 * 2 * 3 = 18. This leaves us with 18 * ∛3. And there you have it! The final simplified answer to the equation 3 * 2 * (9^(2/3)) is 18∛3. We've taken a seemingly complex expression and broken it down into manageable steps, using our understanding of fractional exponents, cube roots, and the order of operations. This journey highlights the power of mathematical thinking: dissecting a problem, applying the right tools, and arriving at a clear and concise solution. By mastering these skills, you'll be well-equipped to tackle any mathematical challenge that comes your way. So, keep practicing, keep exploring, and keep unlocking the secrets of the mathematical universe!

Key Takeaways and Practice Problems

Wow, we've covered a lot, haven't we? Let's recap the key takeaways from our adventure in solving 3 * 2 * (9^(2/3)). First, we learned that fractional exponents represent both powers and roots, with the denominator indicating the type of root and the numerator indicating the power. Second, we explored two methods for simplifying expressions with fractional exponents: squaring first, then finding the cube root, and finding the cube root first, then squaring. Both methods lead to the same result, demonstrating the flexibility of mathematical operations. Third, we emphasized the importance of understanding cube roots and how to factor numbers to simplify radical expressions. Finally, we put it all together to solve the original equation, arriving at the answer 18∛3. To solidify your understanding, here are a few practice problems you can try:

  1. Simplify 4 * 5 * (16^(3/4))
  2. Evaluate 2 * (27^(2/3)) - 1
  3. Calculate (8^(5/3)) / 4

Remember, the key to mastering math is practice! Work through these problems step-by-step, applying the concepts we've discussed. Don't be afraid to make mistakes – they're a natural part of the learning process. And most importantly, have fun exploring the world of numbers and equations! With dedication and a little bit of curiosity, you'll be surprised at what you can achieve. So, go forth and conquer those mathematical challenges!