`root (3)(1331) xx root (3) (216) + root (3) (64)` is equal to

Options

A. 18
B. 79
C. 15
D. 91

Answer

To solve the expression \( \sqrt[3]{1331} \times \sqrt[3]{216} + \sqrt[3]{64} \), we will follow these steps:

### Step 1: Calculate the cube roots individually.
- First, we find \( \sqrt[3]{1331} \).
- Next, we find \( \sqrt[3]{216} \).
- Finally, we find \( \sqrt[3]{64} \).

### Step 2: Calculate \( \sqrt[3]{1331} \).
- We can factor \( 1331 \) as \( 11^3 \).
- Therefore, \( \sqrt[3]{1331} = 11 \).

### Step 3: Calculate \( \sqrt[3]{216} \).
- We can factor \( 216 \) as \( 6^3 \).
- Therefore, \( \sqrt[3]{216} = 6 \).

### Step 4: Calculate \( \sqrt[3]{64} \).
- We can factor \( 64 \) as \( 4^3 \).
- Therefore, \( \sqrt[3]{64} = 4 \).

### Step 5: Substitute the values back into the expression.
- Now, we substitute the calculated cube roots into the original expression:
\[ \sqrt[3]{1331} \times \sqrt[3]{216} + \sqrt[3]{64} = 11 \times 6 + 4 \]

### Step 6: Perform the multiplication.
- Calculate \( 11 \times 6 = 66 \).

### Step 7: Add the result to \( \sqrt[3]{64} \).
- Now, add \( 66 + 4 = 70 \).

### Final Answer:
The final result of the expression \( \sqrt[3]{1331} \times \sqrt[3]{216} + \sqrt[3]{64} \) is \( 70 \).

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