Simplify the expression: x2−1x2+2x+1÷x−1x+1\frac{x^2 - 1}{x^2 + 2x + 1} \div \frac{x - 1}{x + 1}x2+2x+1x2−1÷x+1x−1.
111
x−1x+1\frac{x-1}{x+1}x+1x−1
x+1x−1\frac{x+1}{x-1}x−1x+1
1x+1\frac{1}{x+1}x+11