Firstly, let (x-2)/((x+1)(x-1)2) = A/(x+1) + B/(x-1)+C/(x-1)2, where A,B and C are to be calculated.
Then, multiply both sides of the equation by (x+1)(x-1)2 which will leave an equation as follows;
x-2 = A(x-1)2 + B(x+1)(x-1) +C(x+1). Now let x=1.
-1 = 0A + 0B + 2C this implies C = -1/2
Now let x = -1
-3 = A*(-2)2 + 0B + 0C this implies -3=4*A which means A = -3/4
Now we have equation: x-2 = (-3/4)(x-1)2 + B(x-1)(x+1) -(1/2)(x+1)
If we let x = 0 we get;
-2 = -3/4 -B - 1/2 giving;
-2 = -5/4 - B Adding 5/4 to both sides gives -3/4 = - B from which we can see B = 3/4
now we have transformed our initial fraction into partial fractions;
(x-2)/((x+1)(x-1)2) = -3/4(x+1) + 3/4(x-1) -1/2(x-1)2
To check your answers enter in an arbitrary x, both sides should come to the same number.