Simplify (2mn)^4 / (6m^-3 N^-2) Algebraically

by Andrew McMorgan 46 views

Hey guys, welcome back to Plastik Magazine! Today, we're diving deep into the awesome world of algebra, specifically tackling an expression that might look a bit intimidating at first glance: (2mn)46m−3n−2\frac{(2 m n)^4}{6 m^{-3} n^{-2}}. Don't worry, we're going to break it down step-by-step, making sure you totally get how to simplify this beast. We'll explore the properties of exponents that make this kind of problem a breeze once you know the rules. So, grab your notebooks, maybe a snack, and let's get this done!

Understanding the Core Problem

Alright, let's set the stage. We've got this expression: (2mn)46m−3n−2\frac{(2 m n)^4}{6 m^{-3} n^{-2}}. Our mission, should we choose to accept it (and we totally should!), is to find out which of the given options – A. 8m7n63\frac{8 m^7 n^6}{3}, B. 10m7n63\frac{10 m^7 n^6}{3}, C. 8m16n123\frac{8 m^{16} n^{12}}{3}, or D. m4n63\frac{m^4 n^6}{3} – is equivalent to our original expression. The key here is equivalence, meaning it has the exact same value for all valid inputs. We're given a crucial piece of information: m≠0m \neq 0 and n≠0n \neq 0. This is super important because it means we don't have to worry about dividing by zero, which would be a total disaster! This problem is all about using the rules of exponents to manipulate the expression until it matches one of the choices. Think of it like a puzzle; each rule of exponents is a piece that helps us fit things together.

Let's start by looking at the numerator, (2mn)4(2 m n)^4. When you have a power raised to another power, you multiply the exponents. However, here we have a product raised to a power. The rule for this is that the exponent applies to each factor inside the parentheses. So, (2mn)4(2 m n)^4 becomes 24×m4×n42^4 \times m^4 \times n^4. Calculating 242^4 gives us 2×2×2×2=162 \times 2 \times 2 \times 2 = 16. Therefore, the numerator simplifies to 16m4n416 m^4 n^4. This is our first step in conquering this expression. We've handled the power of a product rule, and now we have a cleaner numerator to work with. It's amazing how a little bit of knowledge about exponent rules can transform a complex-looking term into something much more manageable. Remember this rule: (ab)x=axbx(ab)^x = a^x b^x. It's a fundamental building block for simplifying expressions like this one.

Now, let's turn our attention to the denominator: 6m−3n−26 m^{-3} n^{-2}. This part already looks pretty simplified, but we need to be mindful of those negative exponents. Remember that a negative exponent means you take the reciprocal of the base. So, m−3m^{-3} is equivalent to 1m3\frac{1}{m^3}, and n−2n^{-2} is equivalent to 1n2\frac{1}{n^2}. Putting this back into the denominator, we get 6×1m3×1n26 \times \frac{1}{m^3} \times \frac{1}{n^2}, which is the same as 6m3n2\frac{6}{m^3 n^2}. So, our original expression now looks like 16m4n46m3n2\frac{16 m^4 n^4}{\frac{6}{m^3 n^2}}. This might seem like we've made it more complicated, but we're setting ourselves up to use another key exponent rule: dividing powers with the same base.

The Magic of Exponent Rules

Okay, guys, we've simplified the numerator and the denominator separately. Now, we have our expression in a more organized form: 16m4n46m−3n−2\frac{16 m^4 n^4}{6 m^{-3} n^{-2}}. Let's tackle this division. When dividing terms with the same base, you subtract the exponent in the denominator from the exponent in the numerator. This is a super powerful rule that makes simplifying fractions involving variables so much easier. We'll apply this to the 'm' terms and the 'n' terms separately. So, for the 'm' terms, we have m4m^4 in the numerator and m−3m^{-3} in the denominator. Applying the rule, we get m4−(−3)m^{4 - (-3)}. Remember that subtracting a negative is the same as adding a positive, so 4−(−3)=4+3=74 - (-3) = 4 + 3 = 7. This means our 'm' term becomes m7m^7. Pretty neat, right?

Let's do the same for the 'n' terms. We have n4n^4 in the numerator and n−2n^{-2} in the denominator. So, we calculate n4−(−2)n^{4 - (-2)}. Again, subtracting a negative is adding a positive: 4−(−2)=4+2=64 - (-2) = 4 + 2 = 6. This gives us n6n^6. Awesome! So far, our simplified expression has m7n6m^7 n^6 in the variable part. We're getting really close to finding our answer among the options.

Now, let's not forget about the coefficients, the numbers in front of the variables. We have 16 in the numerator and 6 in the denominator. So, we need to simplify the fraction 166\frac{16}{6}. Both 16 and 6 are divisible by 2. Dividing both by 2, we get 16÷26÷2=83\frac{16 \div 2}{6 \div 2} = \frac{8}{3}. So, the simplified coefficient is 83\frac{8}{3}.

Putting it all together, we combine the simplified coefficient and the simplified variable terms. We have 83\frac{8}{3} as the coefficient, m7m^7 for the 'm' variable, and n6n^6 for the 'n' variable. Therefore, the fully simplified expression is 8m7n63\frac{8 m^7 n^6}{3}. This is the result of carefully applying the rules of exponents. It's crucial to remember each rule: the power of a product rule, and the division of powers with the same base rule, especially when dealing with negative exponents. These rules are your best friends when navigating algebraic simplification.

Connecting to the Options

After all that hard work, we've arrived at our simplified expression: 8m7n63\frac{8 m^7 n^6}{3}. Now, let's look back at the options provided in the question: A. 8m7n63\frac{8 m^7 n^6}{3}, B. 10m7n63\frac{10 m^7 n^6}{3}, C. 8m16n123\frac{8 m^{16} n^{12}}{3}, and D. m4n63\frac{m^4 n^6}{3}.

As you can see, our simplified expression, 8m7n63\frac{8 m^7 n^6}{3}, perfectly matches option A. This means that option A is the expression that is equivalent to the original one. It's so satisfying when all the steps lead you directly to the correct answer, right? We used the property (ab)x=axbx(ab)^x = a^x b^x for the numerator, which turned (2mn)4(2mn)^4 into 24m4n4=16m4n42^4m^4n^4 = 16m^4n^4. Then, we used the rule axay=ax−y\frac{a^x}{a^y} = a^{x-y} for both the 'm' and 'n' variables, which gave us m4−(−3)=m7m^{4 - (-3)} = m^7 and n4−(−2)=n6n^{4 - (-2)} = n^6. Finally, we simplified the coefficients 166\frac{16}{6} by dividing both by their greatest common divisor, 2, resulting in 83\frac{8}{3}.

Let's briefly consider why the other options are incorrect. Option B has the same variable terms but an incorrect coefficient (103\frac{10}{3} instead of 83\frac{8}{3}). This could happen if someone incorrectly simplified 166\frac{16}{6} or made a mistake in the initial power calculation. Option C has incorrect exponents for both 'm' and 'n' (m16n12m^{16} n^{12} instead of m7n6m^7 n^6). This likely arises from incorrectly applying the power rules, perhaps by multiplying the exponents in the numerator (4×4=164 \times 4 = 16 and 4imes3=124 imes 3 = 12) instead of simplifying them correctly, or by misinterpreting the division rule. Option D has an incorrect exponent for 'm' (m4m^4 instead of m7m^7) and the coefficient is also wrong. This suggests a fundamental misunderstanding of how to handle negative exponents and the division of powers.

It's super important to double-check your work, especially when negative exponents are involved. A common mistake is forgetting that subtracting a negative number is the same as adding its positive counterpart. For instance, 4−(−3)4 - (-3) is 4+3=74 + 3 = 7, not 4−3=14 - 3 = 1. Mastering these nuances is key to algebraic success. So, the correct equivalent expression is indeed 8m7n63\frac{8 m^7 n^6}{3}.

Mastering Exponent Rules for Future Success

So, there you have it, guys! We've successfully simplified the complex expression (2mn)46m−3n−2\frac{(2 m n)^4}{6 m^{-3} n^{-2}} and found its equivalent form, which is 8m7n63\frac{8 m^7 n^6}{3}. The journey involved understanding and applying fundamental exponent rules. Let's quickly recap the essential rules we used:

  1. Power of a Product Rule: (ab)x=axbx(ab)^x = a^x b^x. We used this to expand (2mn)4(2mn)^4 into 24m4n4=16m4n42^4m^4n^4 = 16m^4n^4.
  2. Negative Exponent Rule: a−x=1axa^{-x} = \frac{1}{a^x}. This rule is implicitly used when we combine it with the division rule, as seen with m−3m^{-3} and n−2n^{-2}.
  3. Division of Powers Rule: axay=ax−y\frac{a^x}{a^y} = a^{x-y}. This was the workhorse for simplifying our variables. We applied it as m4−(−3)=m7m^{4 - (-3)} = m^7 and n4−(−2)=n6n^{4 - (-2)} = n^6.
  4. Simplifying Coefficients: Always simplify numerical fractions, like 166\frac{16}{6}, by dividing out common factors.

These rules are the bedrock of simplifying algebraic expressions. Practicing with various problems will help you internalize them. Don't be afraid of expressions with negative exponents or multiple variables; break them down piece by piece, just like we did. Think about the properties of exponents as your toolkit – the more comfortable you are with each tool, the more complex problems you can solve. For example, consider a problem like (x2y−3z4)−2(\frac{x^2 y^{-3}}{z^4})^ {-2}. You'd first apply the power of a quotient rule, then the power of a product rule, and finally the negative exponent rule to get everything into a positive exponent form. Each step builds on the last, making the overall simplification process logical and manageable.

Remember, the goal in these types of problems is not just to find the answer but to understand why it's the answer. By understanding the underlying principles – the exponent rules – you gain a powerful skill that applies across many areas of mathematics and science. So, keep practicing, keep questioning, and keep exploring the fascinating world of algebra. You've got this, guys! Let us know in the comments if you have any other tricky algebra problems you'd like us to break down. Until next time, stay curious and keep learning!