Expand `(1- x +x^2) ^(4) ` using binomial expansion.

Explanation

To expand the expression \( (1 - x + x^2)^4 \) using the Binomial Theorem, we can follow these steps:

### Step 1: Identify the terms for the binomial expansion
We can rewrite the expression as \( (a + b)^n \) where:
- \( a = 1 \)
- \( b = -x + x^2 \)
- \( n = 4 \)

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