分式的加减~(x-3)/(x+1)(x-1)=A/(x+1)+B/(x-1),“/”就是分数线了.求A,B的值.
问题描述：
分式的加减~
(x-3)/(x+1)(x-1)=A/(x+1)+B/(x-1),“/”就是分数线了.
求A,B的值.
答
(x+3)/(x+1)(x-1)=A/(x+1)+B/(x-1)→x+3=A(x-1)+B(x+1)→x+3=(A+B)x+(B-A)→A+B=1.B-A=3→A=-1.B=2