Simplify Radicals: Rational Exponent Steps

by Andrew McMorgan 43 views

Hey guys, welcome back to Plastik Magazine! Today, we're diving deep into the awesome world of mathematics, specifically tackling a super common problem that trips a lot of us up: simplifying radical expressions using rational exponents. You know, those times when you see a root symbol and immediately feel a bit intimidated? Well, fret no more! We're going to break down the expression 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2} and show you exactly how to simplify it by rewriting it with rational exponents. This skill is fundamental, and once you've got it down, you'll be cruising through more complex problems in no time. So, grab your notebooks, maybe a snack, and let's get this math party started! We'll explore the different options provided and figure out which one correctly represents the simplified form, and then we'll zero in on that tricky least common denominator of the exponents. It’s going to be a blast!

Understanding Radicals and Rational Exponents

Alright, first things first, let's get on the same page about what we're dealing with. You've got 46\sqrt[6]{4} and 2\sqrt{2}. These are radical expressions. The number under the root symbol is the radicand, and the small number above and to the left of the root symbol is the index. So, in 46\sqrt[6]{4}, 4 is the radicand and 6 is the index. In 2\sqrt{2}, the index is an implied 2 because it's a square root. The cool thing about radicals is that they can be rewritten as rational exponents. This is where the magic happens, guys! The general rule is that amn=amn\sqrt[n]{a^m} = a^{\frac{m}{n}}. Notice how the index 'n' becomes the denominator of the exponent, and the exponent of the radicand 'm' becomes the numerator. This conversion is super handy because it allows us to use all the familiar exponent rules, which are way easier to work with than radical rules for many operations. For our problem, 46\sqrt[6]{4}, we can rewrite 4 as 222^2. So, 46=226\sqrt[6]{4} = \sqrt[6]{2^2}. Applying the conversion rule, this becomes 2262^{\frac{2}{6}}. See? The index 6 is the denominator, and the exponent 2 is the numerator. Now, we can simplify that fraction: 26=13\frac{2}{6} = \frac{1}{3}. So, 46\sqrt[6]{4} is equivalent to 2132^{\frac{1}{3}}. Pretty neat, huh?

Now let's look at 2\sqrt{2}. Remember, the index is 2, and the exponent of the radicand (which is 2) is an implied 1. So, using our rule amn=amn\sqrt[n]{a^m} = a^{\frac{m}{n}}, we get 2=212=212\sqrt{2} = \sqrt[2]{2^1} = 2^{\frac{1}{2}}.

So, our original expression, 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2}, can be rewritten using rational exponents as 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}. This is a crucial first step in simplifying the expression. We've successfully transformed radicals into a form that's much more manageable using exponent rules. Remember this conversion: radical to rational exponent. It's a game-changer!

Evaluating the Options

Now that we've done the heavy lifting of converting the radicals to rational exponents, let's check out the multiple-choice options you guys have been given. Our goal is to find the option that accurately reflects our conversion: 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}.

  • Option A: 225βˆ™2122^{\frac{2}{5}} \bullet 2^{\frac{1}{2}} This option has 2122^{\frac{1}{2}}, which matches our conversion for 2\sqrt{2}. However, the first part is 2252^{\frac{2}{5}}. We calculated 46\sqrt[6]{4} to be 2132^{\frac{1}{3}}, not 2252^{\frac{2}{5}}. So, option A is incorrect. It seems like they might have made a mistake when calculating the rational exponent for the first term, perhaps confusing the index and the exponent in a way that led to the denominator 5 instead of 3. Or maybe they simplified 26\frac{2}{6} incorrectly. It’s a common pitfall, so always double-check your fraction simplification!

  • Option B: 45βˆ™224^5 \bullet 2^2 This option looks completely different from what we derived. The bases are different (4 and 2), and the exponents are integers, not fractions. This doesn't align with our conversion of radicals to rational exponents at all. We converted 46\sqrt[6]{4} to 2132^{\frac{1}{3}} and 2\sqrt{2} to 2122^{\frac{1}{2}}. Option B has 454^5 and 222^2. The base 4 is 222^2, so 45=(22)5=2104^5 = (2^2)^5 = 2^{10}. This is nowhere near 2132^{\frac{1}{3}}. And 222^2 is just 222^2, which is not 2122^{\frac{1}{2}}. So, option B is definitely incorrect. This looks like a misunderstanding of how rational exponents work or perhaps a misinterpretation of the original radical forms.

  • Option C: 415βˆ™2114^{\frac{1}{5}} \bullet 2^{\frac{1}{1}} This option also doesn't match our derived form 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}. The bases are different (4 and 2), and the exponents are incorrect. For instance, 2112^{\frac{1}{1}} is just 2, which is not 2\sqrt{2}. And 4154^{\frac{1}{5}} is (22)15=225(2^2)^{\frac{1}{5}} = 2^{\frac{2}{5}}, which is also not 46\sqrt[6]{4}. So, option C is also incorrect. This option seems to have multiple errors in base and exponent conversion.

Wait a minute, guys! None of the options seem to perfectly match our calculation of 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}. Let's re-examine our steps and the original problem. The problem asks us to simplify 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2} and rewrite using rational exponents. We found 46=213\sqrt[6]{4} = 2^{\frac{1}{3}} and 2=212\sqrt{2} = 2^{\frac{1}{2}}.

Let's revisit the simplification of 46\sqrt[6]{4}. We have 4 inside, which is 222^2. So it's 226\sqrt[6]{2^2}. The rule is amna^{\frac{m}{n}}. Here, a=2a=2, m=2m=2, and n=6n=6. So it's 2262^{\frac{2}{6}}. Simplifying the fraction 26\frac{2}{6} gives 13\frac{1}{3}. So 46=213\sqrt[6]{4} = 2^{\frac{1}{3}}. This is correct.

For 2\sqrt{2}, the base is 2, the exponent is 1, and the index is 2. So it's 2122^{\frac{1}{2}}. This is also correct.

Our expression in rational exponents is indeed 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}.

Now, let's look closely at the options again. It's possible there's a typo in the question's options or my interpretation. However, if we must choose from the given options, let's see if any of them could be derived through a plausible (though possibly incorrect) series of steps. This is a common scenario in tests, unfortunately!

Let's re-evaluate Option A: 225βˆ™2122^{\frac{2}{5}} \bullet 2^{\frac{1}{2}}. The second part, 2122^{\frac{1}{2}}, is correct for 2\sqrt{2}. The first part, 2252^{\frac{2}{5}}, is where the discrepancy lies. We derived 2132^{\frac{1}{3}} for 46\sqrt[6]{4}. Could 25\frac{2}{5} come from somewhere? 46=226\sqrt[6]{4} = \sqrt[6]{2^2}. If we mistakenly thought the index was 5 instead of 6, we'd get 2252^{\frac{2}{5}}. This is a possible error leading to Option A.

Let's re-evaluate Option C: 415βˆ™2114^{\frac{1}{5}} \bullet 2^{\frac{1}{1}}. We can rewrite 4154^{\frac{1}{5}} as (22)15=225(2^2)^{\frac{1}{5}} = 2^{\frac{2}{5}}. The second term 2112^{\frac{1}{1}} is just 2. So Option C is 225βˆ™212^{\frac{2}{5}} \bullet 2^1. This doesn't seem related at all.

Given the choices, and assuming there might be a typo in the question's options or the provided solution, Option A is the closest if we consider a potential error in calculating the exponent for 46\sqrt[6]{4}. However, based on strict mathematical rules, none of the options are correct as written for the expression 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2}.

Let's assume the question intended for one of the options to be correct and try to work backwards or identify the most likely intended answer. If we focus on the question about the least common denominator of the exponents, this implies we need to combine the terms, which requires a common denominator. Our correct rational exponent form is 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}. The exponents are 13\frac{1}{3} and 12\frac{1}{2}.

Finding the Least Common Denominator (LCD)

This is where the problem gets really interesting, guys! The question specifically asks for the least common denominator of the exponents. This is a key concept when you want to add or subtract exponents with different fractional bases, or when you want to express terms with a common fractional exponent structure. In our correctly derived expression 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}, the exponents are 13\frac{1}{3} and 12\frac{1}{2}. To find the least common denominator (LCD) of these fractions, we need to find the smallest positive integer that is a multiple of both denominators, 3 and 2.

The multiples of 3 are: 3, 6, 9, 12, ... The multiples of 2 are: 2, 4, 6, 8, 10, 12, ... The smallest number that appears in both lists is 6. Therefore, the least common denominator of the exponents 13\frac{1}{3} and 12\frac{1}{2} is 6.

Now, let's consider the options provided to see if their exponents lead to a sensible LCD, even if the expressions themselves are wrong. This might give us a clue about the intended question.

  • Option A: 225βˆ™2122^{\frac{2}{5}} \bullet 2^{\frac{1}{2}} The exponents are 25\frac{2}{5} and 12\frac{1}{2}. The denominators are 5 and 2. The LCD of 5 and 2 is 10. This doesn't match our correct LCD of 6.

  • Option B: 45βˆ™224^5 \bullet 2^2 These are not fractional exponents, so the concept of LCD for the exponents doesn't directly apply in the same way. We could write them as 4514^{\frac{5}{1}} and 2212^{\frac{2}{1}}, where the denominators are 1. The LCD would be 1.

  • Option C: 415βˆ™2114^{\frac{1}{5}} \bullet 2^{\frac{1}{1}} Let's convert the bases to be the same. 415=(22)15=2254^{\frac{1}{5}} = (2^2)^{\frac{1}{5}} = 2^{\frac{2}{5}}. And 211=212^{\frac{1}{1}} = 2^1. So the expression is 225βˆ™212^{\frac{2}{5}} \bullet 2^1. The exponents are 25\frac{2}{5} and 1 (or 11\frac{1}{1}). The denominators are 5 and 1. The LCD of 5 and 1 is 5.

This is really puzzling, guys. Our correct derivation for 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2} is 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}, and the LCD of the exponents is 6. None of the options reflect this correctly. Option A has a correct second exponent but an incorrect first exponent (25\frac{2}{5} instead of 13\frac{1}{3}), and its LCD is 10. Option C involves different bases and incorrect exponents, with an LCD of 5.

Let's consider a slight variation of the problem. What if the first term was 45\sqrt[5]{4} instead of 46\sqrt[6]{4}? Then 45=225=225\sqrt[5]{4} = \sqrt[5]{2^2} = 2^{\frac{2}{5}}. If the second term remained 2=212\sqrt{2} = 2^{\frac{1}{2}}, the expression would be 225βˆ™2122^{\frac{2}{5}} \bullet 2^{\frac{1}{2}}. This exactly matches Option A! In this hypothetical case, the exponents are 25\frac{2}{5} and 12\frac{1}{2}. The LCD of 5 and 2 is 10. So if Option A were the correct representation, the LCD would be 10.

What if the question intended for us to simplify 165βˆ™2\sqrt[5]{16} \bullet \sqrt{2}? 165=245=245\sqrt[5]{16} = \sqrt[5]{2^4} = 2^{\frac{4}{5}}. That doesn't match either. What about 425\sqrt[5]{4^2}? That's 165=245\sqrt[5]{16} = 2^{\frac{4}{5}}.

Let's go back to the original problem and assume there's a typo in the options, but the question about the LCD of the exponents is key. The expression is 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2}.

  1. Convert to rational exponents:

    • 46=226=226=213\sqrt[6]{4} = \sqrt[6]{2^2} = 2^{\frac{2}{6}} = 2^{\frac{1}{3}}
    • 2=212\sqrt{2} = 2^{\frac{1}{2}} So the expression is 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}.
  2. Identify the exponents: The exponents are 13\frac{1}{3} and 12\frac{1}{2}.

  3. Find the LCD of the exponents: The denominators are 3 and 2. The LCD is 6.

Conclusion based on the literal problem:

The correct representation of 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2} using rational exponents is 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}. None of the provided options match this exactly. However, if we are forced to choose the option that most closely resembles a potential misinterpretation or typo, Option A (225βˆ™2122^{\frac{2}{5}} \bullet 2^{\frac{1}{2}}) has the correct rational exponent for the second term (2\sqrt{2}) and an exponent for the first term (25\frac{2}{5}) that could arise from a common mistake (e.g., misreading the index or simplifying incorrectly). If Option A were considered correct, the exponents would be 25\frac{2}{5} and 12\frac{1}{2}, and their LCD would be 10.

However, the question also asks: "What is the least common denominator of the exponents?". Based on the correct simplification of 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2} to 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}, the exponents are 13\frac{1}{3} and 12\frac{1}{2}. The least common denominator of these exponents is 6.

It seems there's a disconnect between the provided options for the expression and the direct question about the LCD of the exponents derived from the original expression. Given that the core task is to simplify 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2}, the correct rational exponents are 2132^{\frac{1}{3}} and 2122^{\frac{1}{2}}. The LCD of 13\frac{1}{3} and 12\frac{1}{2} is unquestionably 6.

So, to answer the question precisely:

  • The expression 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2} rewritten using rational exponents is 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}.
  • None of the options A, B, or C are the correct representation of 46βˆ™2\sqrt[6]{4} \bullet \sqrt{2}.
  • The least common denominator of the exponents from the correct rational exponent form (13\frac{1}{3} and 12\frac{1}{2}) is 6.

If this were a test, I'd be raising my hand to ask for clarification! But if forced to pick the best answer related to the LCD, and assuming the original expression is the basis, the LCD is 6. If the question implies that one of the options is the correct form and we need to find the LCD of its exponents, then for Option A (the most plausible typo), the LCD is 10.

Let's assume the question writer intended to test the conversion and the LCD concept accurately. In that case, the focus should be on the LCD of the correctly derived exponents. So, the answer to "What is the least common denominator of the exponents?" should be 6.

To combine our correct form 213βˆ™2122^{\frac{1}{3}} \bullet 2^{\frac{1}{2}}, we would use the LCD of 6 to rewrite the exponents: 213=2262^{\frac{1}{3}} = 2^{\frac{2}{6}} 212=2362^{\frac{1}{2}} = 2^{\frac{3}{6}} So the expression becomes 226βˆ™2362^{\frac{2}{6}} \bullet 2^{\frac{3}{6}}. Using the rule amβˆ™an=am+na^m \bullet a^n = a^{m+n}, we get 226+36=2562^{\frac{2}{6} + \frac{3}{6}} = 2^{\frac{5}{6}}. This final form, 2562^{\frac{5}{6}}, is equivalent to 256=326\sqrt[6]{2^5} = \sqrt[6]{32}.

So, while none of the initial options were correct, the process of finding the LCD is vital for combining terms. The least common denominator of the exponents 13\frac{1}{3} and 12\frac{1}{2} is 6. Stick with the math, guys!