Add: 2xx2−1+1x−1\frac{2x}{x^2 - 1} + \frac{1}{x - 1}x2−12x+x−11
3x+1x2−1\frac{3x + 1}{x^2 - 1}x2−13x+1
2x2+1(x−1)(x+1)\frac{2x^2 + 1}{(x-1)(x+1)}(x−1)(x+1)2x2+1
3x+1(x−1)(x+1)\frac{3x + 1}{(x-1)(x+1)}(x−1)(x+1)3x+1
x+1x−1\frac{x+1}{x-1}x−1x+1