若等式a/(x+1) + b/(x-5)=3x-3/(x+1)(x-1)成立,求实数a,b的值.
问题描述:
若等式a/(x+1) + b/(x-5)=3x-3/(x+1)(x-1)成立,求实数a,b的值.
答
应该是:A/(X+1)+B/(X-5)=(3X-3)/(X+1)(X-5)
二边同乘上:(X+1)(X-5):
A(x-5)+B(x+1)=3x-3
(A+B)x-5A+B=3X-3
A+B=3
-5A+B=-3
A=1,B=2