x/(x+2)-(x+2)/(x-2)=8/(x平方-4)
x/(x+2)-(x+2)/(x-2)-8/{(x+2)(x-2)}=0
{ x(x-2)-(x+2)(x-2)-8} / {(x+2)(x-2)} = 0
{ x^2-2x-x^2+4-8} / {(x+2)(x-2)} = 0
{ -2x-4} / {(x+2)(x-2)} = 0
-2(x+2) / {(x+2)(x-2)} = 0
-2 / (x-2) = 0
无解