(x+2)-(x+1)/(x+1)(x+2)=m/x+1 - n/x+2,mn为常数,则mn=?

问题描述:

(x+2)-(x+1)/(x+1)(x+2)=m/x+1 - n/x+2,mn为常数,则mn=?

(x+2)-(x+1)/(x+1)(x+2)=m/x+1 - n/x+2
(x+2)/(x+1)(x+2)-(x+1)/(x+1)(x+2)=m/x+1 - n/x+2
1/(x+1)-1/(x+2)=m/x+1 - n/x+2
所以m=n=1
mn=1看不懂写出来将等号左边的分数,拆开,成两个分数知道了虽然你写的看不懂但是我会做了