simplify (3x^2 - x - 2) / (x^2 - 1)

factorise the top fraction: 3x^2 - x - 2 = (3x + 2)(x - 1)

factorise the bottom fraction: x^2 -1 = (x + 1)(x - 1)

cancel out the (x - 1) and the final result is (3x + 2) / (x + 1)