Simplify : `(x^(2) - y^(2) + 2xy + 1) - (x^(2) + y^(2) + 4xy - 5)`

Explanation

To simplify the expression `(x^(2) - y^(2) + 2xy + 1) - (x^(2) + y^(2) + 4xy - 5)`, we will follow these steps:

### Step 1: Distribute the negative sign
We start by distributing the negative sign across the second set of parentheses:
\[ (x^2 - y^2 + 2xy + 1) - (x^2 + y^2 + 4xy - 5) = x^2 - y^2 + 2xy + 1 - x^2 - y^2 - 4xy + 5 \]

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