x/(x+3) - 6/(x的平方)-9=1/x -3

答：
x/(x+3) - 6/(x的平方)-9=1/x -3
x/(x+3) -6/(x^2-9)=1/(x-3)
两边同时乘以x^2-9得：
x(x-3)-6=x+3
x^2-3x-6-x-3=0
x^2-4x-9=0
x^2-4x+4=13
(x-2)^2=13
x=2±√13
经检验,x=2±√13是原分式方程的跟