设m和n均不为0,3x^2y^3和-5x^(2+2m+n)y^3是同类项求(3m^3-m^2n+3mn^2+9n^3)\(5m^3+3m^2n-6mn^2+9n^3)的值

设m和n均不为0,3x^2y^3和-5x^(2+2m+n)y^3是同类项求(3m^3-m^2n+3mn^2+9n^3)\(5m^3+3m^2n-6mn^2+9n^3)的值
设m和n均不为0,3x^2y^3和-5x^(2+2m+n)y^3是同类项求(3m^3-m^2n+3mn^2+9n^3)\(5m^3+3m^2n-6mn^2+9n^3)的值

设m和n均不为0,3x^2y^3和-5x^(2+2m+n)y^3是同类项求(3m^3-m^2n+3mn^2+9n^3)\(5m^3+3m^2n-6mn^2+9n^3)的值
3x^2y^3和-5x^(2+2m+n)y^3是同类项,
2=2+2m+n
2m+n=0;
n=-2m
(3m^3-m^2n+3mn^2+9n^3)/(5m^3+3m^2n-6mn^2+9n^3)?
=[3m^3-m^2*(-2m)+3m(-2m)^2+9(-2m)^3]/[5m^3+3m^2*(-2m)-6m(-2m)^2+9(-2m)^3]
=[3m^3+2m^3+12m^3-72m^3]/[5m^3-6m^3-24m^3-72m^3]
=[-55m^3]/[-97m^3]
=55/97