If `r_(1), r_(2), r_(3)` in triangle be in H.P., then the sides are :

Explanation

To solve the problem, we need to establish the relationship between the sides of the triangle and the given condition that \( r_1, r_2, r_3 \) are in Harmonic Progression (H.P.).

### Step-by-Step Solution:

1. **Understanding the Condition**:
Given that \( r_1, r_2, r_3 \) are in H.P., we know that their reciprocals \( \frac{1}{r_1}, \frac{1}{r_2}, \frac{1}{r_3} \) are in Arithmetic Progression (A.P.).

2. **Using the Relationship**:
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