因为(x-4)/(x-5)=[(x-5)+1]/(x-5)=1+1/(x-5)……所以原方程可化为1+1/(x-5)-1-1/(x-6)=1+1/(x-8)-1-1/(x-9)1/(x-5)-1/(x-6)=1/(x-8)-1/(x-9)通分：-1/[（x-5）(x-6)]=-1/[（x-8）(x-9)]（x-5）(x-6)=（x-8）(x-9)x^2...