If ` vec a ,\ vec b ,\ vec c` are position vectors of the vertices `A ,\ B\ a n d\ C` respectively, of a triangle `A B C ,\ ` write the value of ` vec A B+ vec B C+ vec C Adot`

Explanation

To solve the problem, we need to find the value of the sum of the vectors \( \vec{AB} + \vec{BC} + \vec{CA} \).

### Step-by-Step Solution:

1. **Identify the Position Vectors**:
Let the position vectors of points \( A, B, C \) be represented as:
- \( \vec{A} \) for point \( A \)
- \( \vec{B} \) for point \( B \)
...