A train accelerates from rest at a constant rate a for time `t_(1)`and then it retards at the constant rate `b` for time `t_(2)` then comes to rest. Find the ratio `t_(1)`/`t_(2)`.

Explanation

To solve the problem, we will analyze the motion of the train during the two phases: acceleration and deceleration.

### Step-by-Step Solution:

1. **Understanding the Motion Phases**:
- The train starts from rest and accelerates at a constant rate \( a \) for a time \( t_1 \).
- After that, it decelerates (retards) at a constant rate \( b \) for a time \( t_2 \) until it comes to rest.

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