Find the time an aeroplane having velocity `v` takes to fly around a square with side `a` if the wind is blowing at a velocity `u` along one side of the square.\

Explanation

To find the time an aeroplane takes to fly around a square with side length \( a \) while the wind is blowing at a velocity \( u \) along one side of the square, we can break down the problem into several steps.

### Step-by-Step Solution:

1. **Understanding the Problem**:
- The aeroplane has a velocity \( v \).
- The wind is blowing along one side of the square with a velocity \( u \).
- We need to calculate the time taken to fly around the square.
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