Examples with solutions for Root of a Root: Using multiple rules

Exercise #1

Solve the following exercise:

64364= \sqrt[3]{\sqrt{64}}\cdot\sqrt{64}=

Video Solution

Step-by-Step Solution

To solve the expression 64364\sqrt[3]{\sqrt{64}}\cdot\sqrt{64}, we follow these steps:

  • Step 1: Express 64\sqrt{64} as a power:
    Since 64=641/2 \sqrt{64} = 64^{1/2} and 64=26 64 = 2^6 , substituting gives (26)1/2=261/2=23=8 (2^6)^{1/2} = 2^{6 \cdot 1/2} = 2^3 = 8 .
  • Step 2: Express 643\sqrt[3]{\sqrt{64}} as a power:
    Since from Step 1, 64=23=8\sqrt{64} = 2^3 = 8, then 643=83\sqrt[3]{\sqrt{64}} = \sqrt[3]{8}.
    Now, 83=81/3 \sqrt[3]{8} = 8^{1/3} and 8=23 8 = 2^3 , so (23)1/3=231/3=21=2 (2^3)^{1/3} = 2^{3 \cdot 1/3} = 2^1 = 2 .
  • Step 3: Multiply the simplified expressions:
    We now have 643=2 \sqrt[3]{\sqrt{64}} = 2 and 64=8 \sqrt{64} = 8 .
    Thus, 64364=28=16\sqrt[3]{\sqrt{64}} \cdot \sqrt{64} = 2 \cdot 8 = 16.

Therefore, the solution to the problem is 1616.

Answer

16

Exercise #2

Solve the following exercise:

334= \sqrt[4]{\sqrt[3]{3}}=

Video Solution

Step-by-Step Solution

To simplify the given expression, we will use two laws of exponents:

A. Definition of the root as an exponent:

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

B. Law of exponents for an exponent on an exponent:

(am)n=amn (a^m)^n=a^{m\cdot n}

Let's begin simplifying the given expression:

334= \sqrt[4]{\sqrt[3]{3}}= \\ We will use the law of exponents shown in A and first convert the roots in the expression to exponents, we will do this in two steps - in the first step we will convert the inner root in the expression and in the next step we will convert the outer root:

334=3134=(313)14= \sqrt[4]{\sqrt[3]{3}}= \\ \sqrt[4]{3^{\frac{1}{3}}}= \\ (3^{\frac{1}{3}})^{\frac{1}{4}}= We continue and use the law of exponents shown in B, then we will multiply the exponents:

(313)14=31314=31134=3112=312 (3^{\frac{1}{3}})^{\frac{1}{4}}= \\ 3^{\frac{1}{3}\cdot\frac{1}{4}}=\\ 3^{\frac{1\cdot1}{3\cdot4}}=\\ \boxed{3^{\frac{1}{12}}}=\\ \boxed{\sqrt[12]{3}} In the final step we return to writing the root, that is - back, using the law of exponents shown in A (in the opposite direction),

Let's summarize the simplification of the given expression:

334=(313)14=3112=312 \sqrt[4]{\sqrt[3]{3}}= \\ (3^{\frac{1}{3}})^{\frac{1}{4}}= \\ \boxed{3^{\frac{1}{12}}}=\\ \boxed{\sqrt[12]{3}} Therefore, note that the correct answer (most) is answer D.

Answer

Answers a + b

Exercise #3

Solve the following exercise:

3614416= \sqrt{\frac{36}{144}}\cdot\sqrt{\sqrt{16}}=

Video Solution

Step-by-Step Solution

To solve the expression 3614416 \sqrt{\frac{36}{144}} \cdot \sqrt{\sqrt{16}} , follow these steps:

  • Simplify 36144\sqrt{\frac{36}{144}}:
    - Evaluate the fraction: 36144=14\frac{36}{144} = \frac{1}{4}.
    - Take the square root: 14=12\sqrt{\frac{1}{4}} = \frac{1}{2} because 1=1\sqrt{1} = 1 and 4=2\sqrt{4} = 2.
  • Simplify 16\sqrt{\sqrt{16}}:
    - First evaluate the inner square root: 16=4\sqrt{16} = 4 since 42=164^2 = 16.
    - Then take the square root of the result: 4=2\sqrt{4} = 2 since 22=42^2 = 4.
  • Multiply the results from both parts:
    - Multiply the simplified results: 122=1\frac{1}{2} \cdot 2 = 1.

Therefore, the solution to the expression is 11.

Answer

1

Exercise #4

Solve the following exercise:

16643= \sqrt{\frac{16}{\sqrt[3]{64}}}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Calculate the cube root of 64
  • Step 2: Simplify the fraction 16643\frac{16}{\sqrt[3]{64}}
  • Step 3: Simplify result from step 2\sqrt{\text{result from step 2}}

Let's proceed with each step:
Step 1: The cube root of 64 is calculated as follows:
643=4\sqrt[3]{64} = 4. This is because 43=644^3 = 64.

Step 2: Now, simplify the fraction 164\frac{16}{4}:
164=4\frac{16}{4} = 4.

Step 3: Finally, take the square root of the result from step 2:
4=2\sqrt{4} = 2.

Therefore, the solution to the problem is 22.

Answer

2

Exercise #5

Solve the following exercise:

1002525= \sqrt{\sqrt{\frac{100}{25}}}\cdot\sqrt{\sqrt{25}}=

Video Solution

Step-by-Step Solution

To solve this problem, let's evaluate the expression 1002525 \sqrt{\sqrt{\frac{100}{25}}} \cdot \sqrt{\sqrt{25}} step-by-step.

Step 1: Simplify 10025\sqrt{\frac{100}{25}}.
We calculate 10025\frac{100}{25}, which simplifies to 4. Therefore, 10025=4=2\sqrt{\frac{100}{25}} = \sqrt{4} = 2.

Step 2: Now find 4\sqrt{\sqrt{4}}.
4=2\sqrt{4} = 2, so 2\sqrt{2} remains as it is.

Step 3: Simplify 25\sqrt{\sqrt{25}}.
Note that 25=5\sqrt{25} = 5. Therefore, 25=5\sqrt{\sqrt{25}} = \sqrt{5}.

Step 4: Combine the results:
The expression simplifies to 25\sqrt{2} \cdot \sqrt{5}, which is equal to 25=10\sqrt{2 \cdot 5} = \sqrt{10}.

Thus, the final result of the expression is 10\sqrt{10}.

The correct choice from the options provided is: 10 \sqrt{10} .

Answer

10 \sqrt{10}

Exercise #6

Solve the following exercise:

57514= \sqrt[7]{\sqrt{5}}\cdot\sqrt[14]{\sqrt{5}}=

Video Solution

Step-by-Step Solution

To solve the problem of finding 57514\sqrt[7]{\sqrt{5}} \cdot \sqrt[14]{\sqrt{5}}, we will use properties of exponents. Here's how to proceed:

  • Step 1: Express each component using exponent notation.
    57\sqrt[7]{\sqrt{5}} can be expressed as (5)1/7\left(\sqrt{5}\right)^{1/7}.
    5\sqrt{5} itself is expressed as 51/25^{1/2}. Thus, (5)1/7=(51/2)1/7=5(1/2)(1/7)=51/14\left(\sqrt{5}\right)^{1/7} = (5^{1/2})^{1/7} = 5^{(1/2) \cdot (1/7)} = 5^{1/14}.
  • Step 2: Similarly, express 514\sqrt[14]{\sqrt{5}}.
    514\sqrt[14]{\sqrt{5}} can be expressed as (5)1/14\left(\sqrt{5}\right)^{1/14}.
    This can be rewritten as (51/2)1/14=5(1/2)(1/14)=51/28(5^{1/2})^{1/14} = 5^{(1/2) \cdot (1/14)} = 5^{1/28}.
  • Step 3: Multiply the two expressions using the property of exponents multiplying like bases.
    Combine the expressions: 51/1451/28=51/14+1/285^{1/14} \cdot 5^{1/28} = 5^{1/14 + 1/28}.
  • Step 4: Calculate the sum of the exponents.
    114+128=228+128=328\frac{1}{14} + \frac{1}{28} = \frac{2}{28} + \frac{1}{28} = \frac{3}{28}.

This results in 53285^{\frac{3}{28}}. However, upon verification, we note that the correct answer choice in the original problem is 5114+1285^{\frac{1}{14}+\frac{1}{28}}. This suggests 114\frac{1}{14} and 128\frac{1}{28} were to remain as is based on selection of the correct answer, verifying verbatim choice adherence.

Therefore, the correct expression is 5114+1285^{\frac{1}{14}+\frac{1}{28}}.

Answer

5114+128 5^{\frac{1}{14}+\frac{1}{28}}