P,Q and R are three forces acting simultaneously on a particle .`vec(S)` is the vector sum, of the three forces show that if `vec(S)` = 0 , the vector representing these forces form a triangle.

Explanation

To prove that if the vector sum of three forces \( \vec{P}, \vec{Q}, \vec{R} \) acting on a particle is zero, then these vectors form a triangle, we can follow these steps:

### Step 1: Understand the Given Information
We are given three forces \( \vec{P}, \vec{Q}, \vec{R} \) acting on a particle. The vector sum of these forces is represented as:
\[ \vec{S} = \vec{P} + \vec{Q} + \vec{R} \]
It is given that \( \vec{S} = 0 \).
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