The resultant of vectors `vecA=3hati+4hatj+5hatk and vecB =5hati+3 hatj+4hatk` makes an angle `theta` with the X-axis . Evaluate `cos theta`.

Explanation

To solve the problem of finding \( \cos \theta \) for the resultant vector of \( \vec{A} \) and \( \vec{B} \), we will follow these steps:

### Step 1: Write down the vectors
Given:
\[ \vec{A} = 3\hat{i} + 4\hat{j} + 5\hat{k} \]
\[
...