Thực hiện phép tính: (2/x - 2) + (3/x + 2) - (18 - 5x/(x - 2)(x + 2)

1. thuc hien phep tinh
a, ( 2 / x - 2 ) + ( 3 / x + 2 ) - ( 18 - 5x / (x-2)(x+2) )
b, x / xy - y^2 + 2x - y / xy - x^2
c, ( x^2 + 1 / x^2 ) + ( 2 / x(x +1) ) + ( 2 / x )