7m^2n-3mn^2+5m^2n+2mn^2

已知m-n=7,mn=2 求5n-3mn+5m+2 已知mn／m+n=2,求3m-5mn+3n/-m+3mn-n的值 已知mn/m+n=2,求3m-5mn+3n/（-m）+3mn-n 已知M+N分之MN=2,求-m+3mn-n分之3m-5mn+3n 已知mn/m+n=2求3m-5mn+3n/-m+3mn-n 若m-n=4,mn=-1,求(-2mn+m+n)-(3mn+5n-5m)-(m+4n-3mn)的值 -3m^2n/5+m^2n-mn^2 已知MN^2=-6,求-MN(M^2N^5-MN^3-N)的值 急2[mn+(-3m)]-3(2n-mn),m+n=2 mn=-3 3(m^2n+mn)-4(mn-2m^2n)+mn. 3(m^2-mn+2n^2)-2(mn-m^2+n^2)+(5mn-4n^2+1) (a^m)^n*(-a^3m)2n/(a^mn)^5-a^2mn