已知1/a-1/b=5 求2a+3ab-3b/a-2ab-b=?

题目

已知1/a-1/b=5 求2a+3ab-3b/a-2ab-b=?
已知1/a-1/b=5 求(2a+3ab-3b)/(a-2ab-b)=?急

答案

应该是(2a+3ab-2b)/(a-2ab-b)吧
1/a-1/b=5
通分得
b-a=5ab
则(2a+3ab-3b)/(a-2ab-b)
=(2a+3ab-2b)/(a-2ab-b)
=13ab/3ab
=13/3