Simplify: x2−2x−3x2−9\frac{x^2 - 2x - 3}{x^2 - 9}x2−9x2−2x−3
x+3x−1\frac{x+3}{x-1}x−1x+3
x−3x−1\frac{x-3}{x-1}x−1x−3
x−1x−3\frac{x-1}{x-3}x−3x−1
x+1x+3\frac{x+1}{x+3}x+3x+1