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._数学解答

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.

人气：438 ℃　时间：2020-04-14 09:07:57

解答

(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