题目是否是(5-7x)/(x²-1)(x-2)=a/(x-1)+b/(x+1)+c/(x-2)
通分得(5-7x)＝a*(x+1)(x-2)+b*(x-1)(x-2)+c*(x²-1)
a、b、c均为实数
则
a+b+c=0
a+3b=7
2b-2a-c=5
解得
a=1
b=2
c=-3
abc=-6