Question

已知a分之b +b分之a等于m,a分之b-b分之a等于n,则m-n分之1=

Answer 1

1/ m-n=1/(b/a+a/b)-(b/a-a/b)=1/(b/a+a/b+b/a-a/b)(b/a+a/b-b/a+a/b)=1/2b/a*2a/b=1/4