1、化简(x-1/y)/(y-1/x)的结果是2、m-(n²/m-n)*(n-m)/n=?

Question

1、化简(x-1/y)/(y-1/x)的结果是
2、m-(n²/m-n)*(n-m)/n=?

Answer 1

(x-1/y)/(y-1/x)=（xy-1)/y（xy-1)/x=（xy-1)²/xy
m-(n²/m-n)*(n-m)/n=m+n