Solve the Nested Radical: Cube Root of Square Root of 64

Question

Solve the following exercise:

643= \sqrt[3]{\sqrt{64}}=

Video Solution

Solution Steps

00:00 Solve the following problem
00:03 A "regular" root is of the order 2
00:09 When we have a number (A) in a root of the order (B) in a root of the order (C)
00:14 The result equals the number (A) in a root of the order of their product (B times C)
00:18 We will apply this formula to our exercise
00:23 Let's calculate the order of multiplication
00:30 When we have a number (A) to the power of (B) in a root of the order (C)
00:36 The result equals the number (A) to the power of their quotient (B divided by C)
00:39 We will apply this formula to our exercise
00:46 This is the solution

Step-by-Step Solution

To solve this problem, we'll express the nested roots using exponents and then simplify:

We start with the inner expression:

64\sqrt{64} is equivalent to 641/264^{1/2}.

Next, apply the cube root:

641/23\sqrt[3]{64^{1/2}} is equivalent to (641/2)1/3(64^{1/2})^{1/3}.

Using properties of exponents, we simplify the expression:

(641/2)1/3=64(1/2)(1/3)=641/6(64^{1/2})^{1/3} = 64^{(1/2) \cdot (1/3)} = 64^{1/6}.

Now, evaluate 641/664^{1/6}:

Since 64=2664 = 2^6, we have:

641/6=(26)1/6=26(1/6)=21=264^{1/6} = (2^6)^{1/6} = 2^{6 \cdot (1/6)} = 2^{1} = 2.

Therefore, the solution to the exercise 643 \sqrt[3]{\sqrt{64}} is 2\mathbf{2}.

Answer

2