Question

计算（m+2n/n-m）-（n/m-n）+（2m/n-m）要过程

Answer 1

（m-n)^3+(n-m)m^2

=（m-n)^3-(m-n)m^2

=(m-n)[(m-n)^2-m^2]

=(m-n)(m-n+m)(m-n-m)

=-n(m-n)(2m-n)

=-n(2m^2-3mn+n^2)

=-2m^2n+3mn^2-n^3