The angle between two vectors given by `(6hati+6hatk)` and `(7hati+4hatj+4hatk)` is:

Explanation

To find the angle between the two vectors \( \mathbf{A} = 6\hat{i} + 6\hat{k} \) and \( \mathbf{B} = 7\hat{i} + 4\hat{j} + 4\hat{k} \), we will use the formula for the cosine of the angle \( \theta \) between two vectors:

\[ \cos \theta = \frac{\mathbf{A} \cdot \mathbf{B}}{|\mathbf{A}| |\mathbf{B}|} \]

### Step 1: Calculate the dot product \( \mathbf{A} \cdot \mathbf{B} \)

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