Find the direction cosines of the vector joining the points `A(1,2,-3)a n d B(-1,-2,1),` directed from `Aa n dBdot`

Explanation

To find the direction cosines of the vector joining the points A(1, 2, -3) and B(-1, -2, 1), we can follow these steps:

### Step 1: Determine the position vectors of points A and B
The position vector of point A is given by:
\[ \vec{A} = 1\hat{i} + 2\hat{j} - 3\hat{k} \]
The position vector of point B is given by:
...