Equivalent Expression Of √10/√8: Step-by-Step Solution

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Hey guys! Let's break down this math problem together. The question asks: What expression is equivalent to 1084\frac{\sqrt{10}}{\sqrt[4]{8}}? This might seem tricky at first, but don't worry, we'll go through it step by step. We're going to explore how to simplify radical expressions and identify equivalent forms. It's all about manipulating those roots and exponents to get to the right answer. So, grab your pencils, and let's dive in!

Understanding the Problem

Before we jump into solving, let's make sure we understand exactly what the question is asking. The core of the problem lies in simplifying the expression 1084\frac{\sqrt{10}}{\sqrt[4]{8}}. This involves dealing with square roots and fourth roots, which are just fractional exponents in disguise. Remember, x\sqrt{x} is the same as x12x^{\frac{1}{2}}, and x4\sqrt[4]{x} is the same as x14x^{\frac{1}{4}}. The goal is to manipulate this expression using the rules of exponents and radicals to see which of the answer choices (A, B, C, or D) matches our simplified form.

Think of it like this: we're given a fraction with radicals in both the numerator and the denominator. To simplify, we need to find a common ground, which often means expressing everything in terms of the same root or exponent. This might involve rationalizing the denominator, combining terms, or simplifying individual radicals. By the end, we should have a cleaner, more manageable expression that we can easily compare to the given options. This kind of problem is common in algebra and pre-calculus, so mastering these techniques is super valuable!

Breaking Down the Radicals

Okay, let's start by breaking down the radicals individually. This is a crucial step in simplifying complex expressions. We have 10\sqrt{10} in the numerator and 84\sqrt[4]{8} in the denominator. Let's tackle them one at a time.

Simplifying the Numerator: √10

First up, we have 10\sqrt{10}. Can we simplify this further? Well, we need to see if 10 has any perfect square factors. The factors of 10 are 1, 2, 5, and 10. None of these (other than 1) are perfect squares (like 4, 9, 16, etc.). This means 10\sqrt{10} is already in its simplest form. We can't break it down any further. So, for now, we'll leave it as 10\sqrt{10}. Sometimes, the simplest steps are the most important – recognizing when you can't simplify something is just as key as knowing how to simplify!

Simplifying the Denominator: √[4]8

Now, let's focus on the denominator: 84\sqrt[4]{8}. This is a fourth root, meaning we're looking for factors that appear four times. It might not be immediately obvious, but we can rewrite 8 as 232^3. So, we have 234\sqrt[4]{2^3}. To make this easier to work with, let's convert it to exponential form. Remember, xmn\sqrt[n]{x^m} is the same as xmnx^{\frac{m}{n}}. In our case, this means 234\sqrt[4]{2^3} becomes 2342^{\frac{3}{4}}. This exponential form will be super helpful when we combine it with the numerator. By converting radicals to exponents, we can use the rules of exponents to simplify the whole expression more effectively.

Combining and Simplifying the Expression

Alright, we've simplified the numerator and denominator separately. Now it's time to put them back together and see what we can do. We started with 1084\frac{\sqrt{10}}{\sqrt[4]{8}}. We know 10\sqrt{10} is already in its simplest form, and we've rewritten 84\sqrt[4]{8} as 2342^{\frac{3}{4}}. So, our expression now looks like this: 10234\frac{\sqrt{10}}{2^{\frac{3}{4}}}.

This is where things get interesting. To combine these terms, it's helpful to express everything with the same type of exponent or root. Let's convert the numerator, 10\sqrt{10}, to exponential form as well. We know 10\sqrt{10} is the same as 101210^{\frac{1}{2}}. Now our expression is: 1012234\frac{10^{\frac{1}{2}}}{2^{\frac{3}{4}}}. To make the exponents easier to compare, we need a common denominator for the fractions 12\frac{1}{2} and 34\frac{3}{4}. The least common denominator is 4. So, let's rewrite 12\frac{1}{2} as 24\frac{2}{4}. Our expression now becomes 1024234\frac{10^{\frac{2}{4}}}{2^{\frac{3}{4}}}.

But we are not done yet. We have a tricky fraction with exponents. To simplify this further, we need to get creative. One common strategy is to rationalize the denominator or rewrite the base of the numerator to match the base of the denominator if possible. Let's try manipulating the numerator to include a power of 2.

Rationalizing and Final Simplification

Okay, let's think about how to simplify 1024234\frac{10^{\frac{2}{4}}}{2^{\frac{3}{4}}} further. The key here is to get rid of the fractional exponent in the denominator or to find a common base. Since 10 can be written as 2 * 5, let's try rewriting the numerator using this fact. We have 102410^{\frac{2}{4}}, which is the same as (25)24(2 \cdot 5)^{\frac{2}{4}}. Using the power of a product rule, we can rewrite this as 2245242^{\frac{2}{4}} \cdot 5^{\frac{2}{4}}. Now our expression looks like this: 224524234\frac{2^{\frac{2}{4}} \cdot 5^{\frac{2}{4}}}{2^{\frac{3}{4}}}.

Now we have a power of 2 in both the numerator and the denominator, which is great! We can use the quotient rule for exponents, which says that xaxb=xab\frac{x^a}{x^b} = x^{a-b}. So, 224234=22434=214\frac{2^{\frac{2}{4}}}{2^{\frac{3}{4}}} = 2^{\frac{2}{4} - \frac{3}{4}} = 2^{-\frac{1}{4}}. Putting it all together, our expression is now 2145242^{-\frac{1}{4}} \cdot 5^{\frac{2}{4}}. Remember that a negative exponent means we take the reciprocal, so 214=12142^{-\frac{1}{4}} = \frac{1}{2^{\frac{1}{4}}}. And we can simplify 5245^{\frac{2}{4}} to 5125^{\frac{1}{2}}, which is just 5\sqrt{5}. So our expression becomes 5214\frac{\sqrt{5}}{2^{\frac{1}{4}}}.

Now, let's get rid of the fractional exponent in the denominator by multiplying both the numerator and denominator by 2342^{\frac{3}{4}}. This gives us 5234214234=52342\frac{\sqrt{5} \cdot 2^{\frac{3}{4}}}{2^{\frac{1}{4}} \cdot 2^{\frac{3}{4}}} = \frac{\sqrt{5} \cdot 2^{\frac{3}{4}}}{2}.

To match one of the answer choices, let's rewrite 2342^{\frac{3}{4}} as a fourth root: 234=234=842^{\frac{3}{4}} = \sqrt[4]{2^3} = \sqrt[4]{8}. So our expression is now 5842\frac{\sqrt{5} \cdot \sqrt[4]{8}}{2}. We can combine the radicals by expressing \sqrt5} as a fourth root $\sqrt{5 = 5^{\frac{1}{2}} = 5^{\frac{2}{4}} = \sqrt[4]{5^2} = \sqrt[4]{25}$. Now we have 254842\frac{\sqrt[4]{25} \cdot \sqrt[4]{8}}{2}. Multiplying the radicals gives us 25842=20042\frac{\sqrt[4]{25 \cdot 8}}{2} = \frac{\sqrt[4]{200}}{2}.

Conclusion

Wow, we made it! After all that simplification, we found that the expression 1084\frac{\sqrt{10}}{\sqrt[4]{8}} is equivalent to 20042\frac{\sqrt[4]{200}}{2}. This matches answer choice A. Remember, the key to these problems is breaking them down step by step, using the rules of exponents and radicals, and not being afraid to manipulate the expressions until you find a match. You got this!