1/(x-5)+1/(x-9)=1/(x-6)+1/(x+8)通分(2x-14)/(x²-14x+45)=(2x-14)/(x²-14x+48)(2x-14)[1/(x²-14x+45)-1/(x²-14x+48)]=0x²-14x+45≠x²-14x+48所以1/(x²-14x+45)-1/(x²-14x+...