Find the least positive value of n if `((1+i)/(1-i))^n=1.`

Explanation

To solve the problem, we need to find the least positive value of \( n \) such that

\[ \left( \frac{1+i}{1-i} \right)^n = 1. \]

### Step 1: Simplify the expression \(\frac{1+i}{1-i}\)

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