a-b/ab b-c/bc c-a/ca怎么计算
问题描述：
a-b/ab b-c/bc c-a/ca怎么计算
答
a-b/ab=a/ab-b/ab=1/b-1/a
b-c/bc=b/bc-c/bc=1/c-1/b
c-a/ca=c/ac-a/ac=1/a-1/c