Question

m分之1+n分之1=m+n分之1求m分之n+n分之m的值

Answer 1

1/m+1/n=(m+n)/mn=1/(m+n)

mn=(m+n)^2=m^2+n^2+2mn

mn=-(m^+n^2)

n/m+m/n=(m^2+n^2)/mn

=-1