Simplify This Exponential Expression!

by Andrew McMorgan 38 views

Hey guys, ever stare at a math problem and feel like your brain just did a hard reset? I know I have! Today, we're diving deep into simplifying exponential expressions, specifically tackling one that looks a bit gnarly: (256 imes 64)^{ rac{1}{4}}. Don't sweat it; by the end of this, you'll be a pro at breaking these down. We're going to explore how to manipulate these numbers using the magic of exponents and roots to find the real answer among the options provided. Get ready to flex those math muscles because we're not just finding an answer; we're understanding the why behind it. We'll break down the properties of exponents, how they interact with roots, and how to make those big numbers a lot more manageable. Think of it as decoding a secret mathematical message. We'll be using key properties like (ab)n=anbn(ab)^n = a^n b^n and a^{ rac{m}{n}} = oots[n]{a^m}. So grab your favorite beverage, get comfy, and let's unravel this mathematical puzzle together. We'll walk through the steps methodically, ensuring that no one gets left behind. This isn't just about solving one problem; it's about building a foundational understanding that will help you tackle countless others. We'll look at prime factorization, the power of fractional exponents, and how to simplify radicals. You'll see that often, the most intimidating problems are just a series of simpler steps waiting to be discovered. Let's get started on this awesome journey of mathematical discovery!

Unpacking the Problem: (256 imes 64)^{ rac{1}{4}}

Alright, let's get down to business with our main challenge: (256 imes 64)^{ rac{1}{4}}. This expression, at first glance, might make you want to reach for the nearest calculator. But hold up! The beauty of math is that we can often simplify these things without needing any fancy gadgets. The rac{1}{4} exponent outside the parentheses means we need to take the fourth root of the entire product inside. So, we're looking for a number that, when multiplied by itself four times, equals 256imes64256 imes 64. Pretty wild, right? The key here is to recognize that both 256 and 64 are powers of 2. This is a huge clue! If we can express them as powers of 2, things will get a whole lot easier. Remember, 256=28256 = 2^8 and 64=2664 = 2^6. So, our expression can be rewritten as (2^8 imes 2^6)^{ rac{1}{4}}. Now, we can use the exponent rule amimesan=am+na^m imes a^n = a^{m+n}. Applying this, we get (2^{8+6})^{ rac{1}{4}} = (2^{14})^{ rac{1}{4}}. Next, we use another crucial exponent rule: (am)n=amimesn(a^m)^n = a^{m imes n}. So, (2^{14})^{ rac{1}{4}} = 2^{14 imes rac{1}{4}} = 2^{ rac{14}{4}}. We can simplify the exponent rac{14}{4} by dividing both the numerator and denominator by 2, which gives us rac{7}{2}. So, our expression simplifies to 2^{ rac{7}{2}}. Now, this is a correct simplification, but it's not in the format of the multiple-choice answers provided. The answers involve a whole number multiplied by a fourth root. This means we need to manipulate 2^{ rac{7}{2}} further. The exponent rac{7}{2} can be thought of as 3 + rac{1}{2}, so 2^{ rac{7}{2}} = 2^{3 + rac{1}{2}} = 2^3 imes 2^{ rac{1}{2}} = 8 imes oots{2}. Hmm, this is still not matching the format of the options, which all have a oots[4] oots[4]{} term. Let's backtrack a bit and approach 2^{ rac{14}{4}} differently, keeping the fourth root in mind. We have 2^{ rac{14}{4}} = 2^{ rac{12+2}{4}} = 2^{ rac{12}{4} + rac{2}{4}} = 2^3 imes 2^{ rac{2}{4}} = 8 imes 2^{ rac{1}{2}}. Okay, this is the same result as before. This suggests we might need to express the original numbers (256 and 64) in a way that directly helps us with the fourth root. Let's reconsider 256256 and 6464. We know 256=44256 = 4^4 and 64=4364 = 4^3. So, (256 imes 64)^{ rac{1}{4}} = (4^4 imes 4^3)^{ rac{1}{4}} = (4^{4+3})^{ rac{1}{4}} = (4^7)^{ rac{1}{4}} = 4^{ rac{7}{4}}. This is getting closer to the format with a fourth root. Now, let's rewrite 4^{ rac{7}{4}} as 4^{ rac{4+3}{4}} = 4^{ rac{4}{4} + rac{3}{4}} = 4^1 imes 4^{ rac{3}{4}} = 4 imes oots[4]{4^3} = 4 imes oots[4]{64}. This still doesn't perfectly match the structure of the options. Let's try expressing everything in terms of base 2 again, but with a focus on getting terms that can be simplified by the fourth root. We had (2^{14})^{ rac{1}{4}}. We want to see if we can pull out groups of four 22s. 214=212imes222^{14} = 2^{12} imes 2^2. So, (2^{14})^{ rac{1}{4}} = (2^{12} imes 2^2)^{ rac{1}{4}}. Using the property (ab)n=anbn(ab)^n = a^n b^n, this becomes (2^{12})^{ rac{1}{4}} imes (2^2)^{ rac{1}{4}} = 2^{12 imes rac{1}{4}} imes 2^{2 imes rac{1}{4}} = 2^3 imes 2^{ rac{2}{4}} = 8 imes 2^{ rac{1}{2}}. This is persistent! What if we rethink the initial values? 256=28256 = 2^8. 64=2664 = 2^6. So we have (2^8 imes 2^6)^{ rac{1}{4}}. Let's apply the fourth root to each factor individually first. 256^{ rac{1}{4}} = (2^8)^{ rac{1}{4}} = 2^{8/4} = 2^2 = 4. And 64^{ rac{1}{4}} = (2^6)^{ rac{1}{4}} = 2^{6/4} = 2^{ rac{3}{2}}. So, the expression is 4 imes 2^{ rac{3}{2}}. This is 4 imes 2^{1 + rac{1}{2}} = 4 imes (2^1 imes 2^{ rac{1}{2}}) = 4 imes 2 imes oots{2} = 8 imes oots{2}. Still not matching. Let's look at the options for a clue. They all have a structure like Ximesoots[4]YX imes oots[4]{Y}. This means we need to isolate a part of 2142^{14} that is a perfect fourth power. We have 2142^{14}. We can write 1414 as 12+212 + 2. So 214=212imes222^{14} = 2^{12} imes 2^2. Then (2^{14})^{ rac{1}{4}} = (2^{12} imes 2^2)^{ rac{1}{4}} = (2^{12})^{ rac{1}{4}} imes (2^2)^{ rac{1}{4}} = 2^{12/4} imes 2^{2/4} = 2^3 imes 2^{1/2} = 8 imes oots{2}. Still the same. Let's try writing 1414 differently to get a fourth root term. Maybe 14=8+614 = 8 + 6? (2^8 imes 2^6)^{ rac{1}{4}} = (2^8)^{ rac{1}{4}} imes (2^6)^{ rac{1}{4}} = 2^{8/4} imes 2^{6/4} = 2^2 imes 2^{3/2} = 4 imes 2^{3/2}. We already did this. Okay, let's think about the numbers 256 and 64 differently. What if we express them as powers of 4? 256=44256 = 4^4. 64=4imes16=4imes42=4364 = 4 imes 16 = 4 imes 4^2 = 4^3. So (256 imes 64)^{ rac{1}{4}} = (4^4 imes 4^3)^{ rac{1}{4}} = (4^7)^{ rac{1}{4}}. This is 47/44^{7/4}. Now we need to express this in the form Ximesoots[4]YX imes oots[4]{Y}. We can write 47/4=44/4+3/4=41imes43/4=4imesoots[4]43=4imesoots[4]644^{7/4} = 4^{4/4 + 3/4} = 4^1 imes 4^{3/4} = 4 imes oots[4]{4^3} = 4 imes oots[4]{64}. This is close but not one of the options. Let's try expressing 256 and 64 differently. 256=162256 = 16^2. 64=82=4364 = 8^2 = 4^3. Let's stick to base 2. 256=28256 = 2^8. 64=2664 = 2^6. So we have (2^8 imes 2^6)^{ rac{1}{4}} = (2^{14})^{ rac{1}{4}}. We need to get a oots[4] oots[4]{} term. This means we need an exponent that is not divisible by 4. Let's split 2142^{14} into 212imes222^{12} imes 2^2. So (2^{12} imes 2^2)^{ rac{1}{4}} = (2^{12})^{ rac{1}{4}} imes (2^2)^{ rac{1}{4}} = 2^{12/4} imes 2^{2/4} = 2^3 imes 2^{1/2} = 8 imes oots{2}. This is consistently what we get. Let's re-examine the options. They are: A. 4imesoots[4]44 imes oots[4]{4}, B. 2imesoots[4]22 imes oots[4]{2}, C. 8imesoots[4]48 imes oots[4]{4}, D. 8imesoots[4]28 imes oots[4]{2}. My result is 8imesoots28 imes oots{2}. This can be written as 8 imes 2^{ rac{1}{2}}. The options have fourth roots. This means something is off in my approach or understanding of how to match the format. Let's go back to the very beginning and break down 256 and 64 into their prime factors and see if we can group them into fours. 256=2imes128=2imes2imes64=2imes2imes2imes32=24imes25=29256 = 2 imes 128 = 2 imes 2 imes 64 = 2 imes 2 imes 2 imes 32 = 2^4 imes 2^5 = 2^9. Oh wait, 256=28256 = 2^8. My previous calculation was correct. 64=2664 = 2^6. So (2^8 imes 2^6)^{ rac{1}{4}} = (2^{14})^{ rac{1}{4}}. Let's try splitting 2142^{14} to get a number that is divisible by 4, and a remainder. 14extdividedby4extis3extwitharemainderof214 ext{ divided by } 4 ext{ is } 3 ext{ with a remainder of } 2. So 214=24imes3+2=212imes222^{14} = 2^{4 imes 3 + 2} = 2^{12} imes 2^2. Then (2^{14})^{ rac{1}{4}} = (2^{12} imes 2^2)^{ rac{1}{4}} = (2^{12})^{ rac{1}{4}} imes (2^2)^{ rac{1}{4}} = 2^{12/4} imes 2^{2/4} = 2^3 imes 2^{1/2} = 8 imes oots{2}. This is consistently the answer. Let's check the options again. Option D is 8imesoots[4]28 imes oots[4]{2}. This is 8imes21/48 imes 2^{1/4}. My answer is 8imes21/28 imes 2^{1/2}. These are not the same. There must be a mistake in my prime factorization or exponent rules application. Let me re-calculate. 256=28256 = 2^8. 64=2664 = 2^6. (256 imes 64)^{ rac{1}{4}} = (2^8 imes 2^6)^{ rac{1}{4}} = (2^{14})^{ rac{1}{4}}. This step is solid. Now, applying the outer exponent: 2^{14 imes rac{1}{4}} = 2^{ rac{14}{4}} = 2^{ rac{7}{2}}. This is also solid. So the expression equals 2^{ rac{7}{2}}. Now, how to represent 2^{ rac{7}{2}} in the form Ximesoots[4]YX imes oots[4]{Y}? We have 2^{ rac{7}{2}} = 2^{3.5}. The options have a oots[4] oots[4]{} which means a power of 1/41/4. Let's look at 2^{ rac{7}{2}} and try to get a fourth power term. 2^{ rac{7}{2}} = oots{2^7} = oots{128}. This is not helpful for getting a fourth root. What if we write 2^{ rac{7}{2}} with a denominator of 4 in the exponent? rac{7}{2} = rac{14}{4}. So we have 2^{ rac{14}{4}}. This means (2^{14})^{ rac{1}{4}} = oots[4]{2^{14}}. Now, we need to simplify oots[4]214 oots[4]{2^{14}}. We look for the largest multiple of 4 that is less than or equal to 14, which is 12. So, 214=212imes222^{14} = 2^{12} imes 2^2. Therefore, oots[4]214=oots[4]212imes22=oots[4]212imesoots[4]22 oots[4]{2^{14}} = oots[4]{2^{12} imes 2^2} = oots[4]{2^{12}} imes oots[4]{2^2}. We know that oots[4]212=212/4=23=8 oots[4]{2^{12}} = 2^{12/4} = 2^3 = 8. And oots[4]22=22/4=21/2=oots2 oots[4]{2^2} = 2^{2/4} = 2^{1/2} = oots{2}. So the expression is 8imesoots28 imes oots{2}. Again, 8imesoots28 imes oots{2}. Why doesn't this match the options which have oots[4] oots[4]{}? Let me re-read the options and the problem. It's possible I'm misinterpreting the format or the options themselves. Option D is 8imesoots[4]28 imes oots[4]{2}. This equals 8imes21/48 imes 2^{1/4}. My result is 8imes21/28 imes 2^{1/2}. There's a factor of 21/42^{1/4} difference. Let me restart with a clean slate, focusing on the structure of the answers. The answers are Ximesoots[4]YX imes oots[4]{Y}. This means we need to pull out a fourth power from 2142^{14}. We found 214=212imes222^{14} = 2^{12} imes 2^2. So (2^{14})^{ rac{1}{4}} = 8 imes oots[4]{2^2}. Wait, oots[4]22=oots[4]4 oots[4]{2^2} = oots[4]{4}. So the answer is 8imesoots[4]48 imes oots[4]{4}. This matches option C! Let's verify this. (256 imes 64)^{ rac{1}{4}} = (2^8 imes 2^6)^{ rac{1}{4}} = (2^{14})^{ rac{1}{4}} = 2^{ rac{14}{4}} = 2^{ rac{7}{2}}. To express 2^{ rac{7}{2}} as 8imesoots[4]48 imes oots[4]{4}: 8imesoots[4]4=23imes41/4=23imes(22)1/4=23imes22/4=23imes21/2=23+1/2=27/28 imes oots[4]{4} = 2^3 imes 4^{1/4} = 2^3 imes (2^2)^{1/4} = 2^3 imes 2^{2/4} = 2^3 imes 2^{1/2} = 2^{3 + 1/2} = 2^{7/2}. YES! It matches. My mistake was in simplifying oots[4]22 oots[4]{2^2} to oots2 oots{2} and not recognizing that oots[4]4 oots[4]{4} is the form needed. oots[4]22 oots[4]{2^2} is indeed oots[4]4 oots[4]{4}. The key was realizing that 214=212imes222^{14} = 2^{12} imes 2^2, leading to (2^{12})^{ rac{1}{4}} imes (2^2)^{ rac{1}{4}} = 2^3 imes oots[4]{2^2} = 8 imes oots[4]{4}. So option C is the correct one.

Method 1: Prime Factorization and Exponent Rules

Let's break down this problem using the power of prime factorization and exponent rules, guys. Our expression is (256 imes 64)^{ rac{1}{4}}. The first move is to express 256 and 64 as powers of their smallest prime factor, which is 2. We know that 256=28256 = 2^8 and 64=2664 = 2^6. Substituting these into our expression, we get: (2^8 imes 2^6)^{ rac{1}{4}}. Now, we use the rule of exponents that states amimesan=am+na^m imes a^n = a^{m+n}. Adding the exponents inside the parentheses, we have: (2^{8+6})^{ rac{1}{4}} = (2^{14})^{ rac{1}{4}}. The next step involves the rule (am)n=amimesn(a^m)^n = a^{m imes n}. Multiplying the exponents, we get: 2^{14 imes rac{1}{4}} = 2^{ rac{14}{4}}. We can simplify the fraction in the exponent: rac{14}{4} = rac{7}{2}. So, our expression is equivalent to 2^{ rac{7}{2}}. Now, we need to match this to one of the answer choices, which are in the form Ximesoots[4]YX imes oots[4]{Y}. To get a fourth root, we need an exponent with a denominator of 4. Let's rewrite rac{7}{2} with a denominator of 4: rac{7}{2} = rac{7 imes 2}{2 imes 2} = rac{14}{4}. So, we have 2^{ rac{14}{4}}. This can be written as (2^{14})^{ rac{1}{4}}, which is oots[4]214 oots[4]{2^{14}}. To simplify this, we look for the largest multiple of 4 that is less than or equal to 14. That's 12. So, we can rewrite 2142^{14} as 212imes222^{12} imes 2^2. Now, our expression becomes: oots[4]212imes22 oots[4]{2^{12} imes 2^2}. Using the property oots[n]ab=oots[n]aimesoots[n]b oots[n]{ab} = oots[n]{a} imes oots[n]{b}, we can split this: oots[4]212imesoots[4]22 oots[4]{2^{12}} imes oots[4]{2^2}. We can simplify the first part: oots[4]{2^{12}} = 2^{ rac{12}{4}} = 2^3 = 8. The second part is oots[4]22 oots[4]{2^2}. So, our expression is 8imesoots[4]228 imes oots[4]{2^2}. Since 22=42^2 = 4, this is 8imesoots[4]48 imes oots[4]{4}. This exactly matches option C. So, the correct answer is 8imesoots[4]48 imes oots[4]{4}. This method is super effective because it breaks down complex numbers into manageable powers and then uses fundamental exponent rules to simplify.

Method 2: Using Properties of Roots Directly

Let's try another approach, focusing more directly on the properties of roots. We start with (256 imes 64)^{ rac{1}{4}}. The exponent rac{1}{4} means we're taking the fourth root of the product. So, we can rewrite this as oots[4]256imes64 oots[4]{256 imes 64}. Using the property that oots[n]aimesb=oots[n]aimesoots[n]b oots[n]{a imes b} = oots[n]{a} imes oots[n]{b}, we can separate the roots: oots[4]256imesoots[4]64 oots[4]{256} imes oots[4]{64}. Now, we need to find the fourth root of 256 and the fourth root of 64. Let's think about what number multiplied by itself four times gives 256. We know 44=4imes4imes4imes4=16imes16=2564^4 = 4 imes 4 imes 4 imes 4 = 16 imes 16 = 256. So, oots[4]256=4 oots[4]{256} = 4. Now, let's consider oots[4]64 oots[4]{64}. This one is a bit trickier because 64 isn't a perfect fourth power of an integer. However, we know 64=4imes16=4imes42=4364 = 4 imes 16 = 4 imes 4^2 = 4^3. So, oots[4]64=oots[4]43 oots[4]{64} = oots[4]{4^3}. This doesn't immediately simplify to an integer. Let's go back to expressing 64 in terms of its prime factors: 64=2664 = 2^6. So, oots[4]64=oots[4]26 oots[4]{64} = oots[4]{2^6}. Using the property oots[n]{a^m} = a^{ rac{m}{n}}, we get 2^{ rac{6}{4}} = 2^{ rac{3}{2}}. So, the expression becomes 4 imes 2^{ rac{3}{2}}. This is correct, but again, not in the format of the options. Let's reconsider oots[4]64 oots[4]{64}. We know 64=2664 = 2^6. We want to see if we can extract a fourth power. 26=24imes222^6 = 2^4 imes 2^2. So, oots[4]64=oots[4]24imes22=oots[4]24imesoots[4]22=2imesoots[4]22=2imesoots[4]4 oots[4]{64} = oots[4]{2^4 imes 2^2} = oots[4]{2^4} imes oots[4]{2^2} = 2 imes oots[4]{2^2} = 2 imes oots[4]{4}. Now, let's put it all together. The original expression was oots[4]256imesoots[4]64 oots[4]{256} imes oots[4]{64}. We found oots[4]256=4 oots[4]{256} = 4 and oots[4]64=2imesoots[4]4 oots[4]{64} = 2 imes oots[4]{4}. So, the product is 4imes(2imesoots[4]4)=(4imes2)imesoots[4]4=8imesoots[4]44 imes (2 imes oots[4]{4}) = (4 imes 2) imes oots[4]{4} = 8 imes oots[4]{4}. This again leads us to option C. This method is useful when you can easily identify the roots of the individual factors. Sometimes, like with oots[4]64 oots[4]{64}, you might need to break it down further to match the required format.

Method 3: Expressing in a Common Base and Manipulating Exponents

Let's explore a third way to tackle this, which involves expressing everything in a common base and then carefully manipulating the exponents to fit the answer format. We have (256 imes 64)^{ rac{1}{4}}. We already established that 256=28256 = 2^8 and 64=2664 = 2^6. So the expression is (2^8 imes 2^6)^{ rac{1}{4}} = (2^{14})^{ rac{1}{4}} = 2^{ rac{14}{4}} = 2^{ rac{7}{2}}. Now, look at the options: they all have a structure of a whole number multiplied by a fourth root (oots[4] oots[4]{}). This means we want to express 2^{ rac{7}{2}} in the form 2aimes2b2^a imes 2^b where aa is an integer and bb is a fraction with a denominator of 4. We have 2^{ rac{7}{2}}. To get a denominator of 4, we rewrite the exponent: rac{7}{2} = rac{14}{4}. So we have 2^{ rac{14}{4}}. We want to separate this into an integer exponent and a fractional exponent with denominator 4. The largest integer exponent we can get by dividing 14 by 4 is 3 (since 4imes3=124 imes 3 = 12). The remainder is 14−12=214 - 12 = 2. So, we can write rac{14}{4} = rac{12}{4} + rac{2}{4} = 3 + rac{2}{4}. Therefore, 2^{ rac{14}{4}} = 2^{3 + rac{2}{4}} = 2^3 imes 2^{ rac{2}{4}}. Now, 23=82^3 = 8. And 2^{ rac{2}{4}} = 2^{ rac{1}{2}}. Wait, this leads back to 8 imes 2^{ rac{1}{2}} = 8 imes oots{2}. Let me re-examine the exponent split. We need the fractional part to have a denominator of 4 after simplification if possible, or to directly represent the fourth root term. We have 2^{ rac{14}{4}}. We want to express it as 2aimesoots[4]2b2^a imes oots[4]{2^b}. Here aa would be the integer part of rac{14}{4} when expressed as a mixed number, and bb would be the remainder. rac{14}{4} = 3 with a remainder of 22. So, 2^{ rac{14}{4}} = 2^3 imes 2^{ rac{2}{4}}. This equals 8 imes 2^{ rac{2}{4}}. Now, 2^{ rac{2}{4}} is a term that can be put under a fourth root. 2^{ rac{2}{4}} = oots[4]{2^2}. So, the expression is 8imesoots[4]228 imes oots[4]{2^2}. Since 22=42^2 = 4, this is 8imesoots[4]48 imes oots[4]{4}. This is option C. The key here is to ensure the fractional exponent part, when put under the root, results in a form matching the options. 2^{ rac{2}{4}} is indeed oots[4]22 oots[4]{2^2}. This method shows how to manipulate exponents to match the desired format of the answer choices.

Final Answer and Verification

After exploring multiple methods, we consistently arrive at the same answer: 8imesoots[4]48 imes oots[4]{4}. Let's quickly verify why the other options are incorrect. Option A is 4imesoots[4]4=22imes41/4=22imes(22)1/4=22imes22/4=22imes21/2=22.5=25/24 imes oots[4]{4} = 2^2 imes 4^{1/4} = 2^2 imes (2^2)^{1/4} = 2^2 imes 2^{2/4} = 2^2 imes 2^{1/2} = 2^{2.5} = 2^{5/2}. This is not 27/22^{7/2}. Option B is 2imesoots[4]2=21imes21/4=21+1/4=25/42 imes oots[4]{2} = 2^1 imes 2^{1/4} = 2^{1 + 1/4} = 2^{5/4}. This is not 27/22^{7/2}. Option D is 8imesoots[4]2=23imes21/4=23+1/4=213/48 imes oots[4]{2} = 2^3 imes 2^{1/4} = 2^{3 + 1/4} = 2^{13/4}. This is not 27/22^{7/2}. Our calculated value for option C is 8imesoots[4]4=23imes41/4=23imes(22)1/4=23imes22/4=23imes21/2=23.5=27/28 imes oots[4]{4} = 2^3 imes 4^{1/4} = 2^3 imes (2^2)^{1/4} = 2^3 imes 2^{2/4} = 2^3 imes 2^{1/2} = 2^{3.5} = 2^{7/2}. This perfectly matches our simplified expression. So, the correct answer is C. 8imesoots[4]48 imes oots[4]{4}.