Simplify the Radical Expression: Fourth Root of 2 Divided by Fifth Root of 2

Radical Expressions with Fractional Exponents

Solve the following exercise:

2425= \frac{\sqrt[4]{2}}{\sqrt[5]{2}}=

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Simplify the following problem
00:03 Every number is to the power of 1
00:12 When we have a root of the order (B) on number (X) to the power of (A)
00:16 The result equals number (X) to the power of (A divided by B)
00:25 Apply this formula to our exercise
00:35 When we have division of powers (A\B) with equal bases
00:41 The result equals the common base to the power of the difference of the exponents (A - B)
00:44 Apply this formula to our exercise
00:53 Determine the common denominator and calculate the power
00:59 This is the solution

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

Solve the following exercise:

2425= \frac{\sqrt[4]{2}}{\sqrt[5]{2}}=

2

Step-by-step solution

Express the definition of root as a power:

an=a1n \sqrt[n]{a}=a^{\frac{1}{n}}

Apply this definition and proceed to convert the roots in the problem:

2425=214215 \frac{\sqrt[4]{2}}{\sqrt[5]{2}}= \frac{2^{\frac{1}{4}}}{2^{\frac{1}{5}}}

Below is the law of powers for division with identical bases:

aman=amn \frac{a^m}{a^n}=a^{m-n}

Let's apply this law to our problem:

214215=21415 \frac{2^{\frac{1}{4}}}{2^{\frac{1}{5}}}=2^{\frac{1}{4}-\frac{1}{5}}

In order to not overly complicate our calculations proceed to solve the expression in the power numerator from the last step separately and calculate the value of the fraction:

1415=514120=5420=120 \frac{1}{4}-\frac{1}{5}=\frac{5\cdot1-4\cdot1}{20}=\\ \frac{5-4}{20}=\frac{1}{20}

In the first step, we combined the two fractions into one fraction line, by expanding to the common denominator of 20 and performing the subtraction operation. (In the first fraction on the left we expanded both the numerator and denominator by 5, and in the second fraction we expanded both the numerator and denominator by 4) We then proceeded to simplify the resulting expression,

Returning once more to our problem, consider the result of the subtraction operation between the fractions that we just performed, as shown below:

21415=2120 2^{\frac{1}{4}-\frac{1}{5}}=2^{\frac{1}{20}}

Summarize the various steps of the solution:

2425=21415=2120 \frac{\sqrt[4]{2}}{\sqrt[5]{2}}=2^{\frac{1}{4}-\frac{1}{5}}=2^{\frac{1}{20}}

Therefore, the correct answer is answer C.

3

Final Answer

2120 2^{\frac{1}{20}}

Key Points to Remember

Essential concepts to master this topic
  • Rule: Convert radicals to fractional exponents: an=a1n \sqrt[n]{a} = a^{\frac{1}{n}}
  • Technique: Use division rule aman=amn \frac{a^m}{a^n} = a^{m-n} for same bases
  • Check: Verify 1415=5420=120 \frac{1}{4} - \frac{1}{5} = \frac{5-4}{20} = \frac{1}{20}

Common Mistakes

Avoid these frequent errors
  • Dividing the root indices instead of subtracting exponents
    Don't divide 4÷5 = 4/5 thinking the answer is 245 2^{\frac{4}{5}} ! This ignores the exponent rules for division. Always convert to fractional exponents first, then subtract: 214÷215=21415 2^{\frac{1}{4}} ÷ 2^{\frac{1}{5}} = 2^{\frac{1}{4} - \frac{1}{5}} .

Practice Quiz

Test your knowledge with interactive questions

Solve the following exercise:

\( \sqrt{\frac{2}{4}}= \)

FAQ

Everything you need to know about this question

Why do I need to convert radicals to fractional exponents?

+

Converting to fractional exponents lets you use the power rules you already know! 24=214 \sqrt[4]{2} = 2^{\frac{1}{4}} is much easier to work with when dividing.

How do I subtract fractions with different denominators?

+

Find the common denominator! For 1415 \frac{1}{4} - \frac{1}{5} , the LCD is 20. Convert: 520420=120 \frac{5}{20} - \frac{4}{20} = \frac{1}{20} .

Can I leave my answer as a radical instead of an exponent?

+

Yes! 2120 2^{\frac{1}{20}} can also be written as 220 \sqrt[20]{2} . Both forms are correct, but fractional exponents are often preferred in algebra.

What if the bases were different numbers?

+

If the bases are different (like 3425 \frac{\sqrt[4]{3}}{\sqrt[5]{2}} ), you cannot use the division rule for exponents. The bases must be the same to combine exponents.

How do I check if my final answer is correct?

+

Convert back to radical form and use a calculator! 2120=2201.035 2^{\frac{1}{20}} = \sqrt[20]{2} \approx 1.035 . Then check: 24251.1891.1491.035 \frac{\sqrt[4]{2}}{\sqrt[5]{2}} \approx \frac{1.189}{1.149} \approx 1.035

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Rules of Roots questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations