(x＋2y＋2m)(2x－y＋n)=2x^2-xy+nx+4xy-2y^2+2ny+4mx-2my+2mn=2x^2+3xy-2y^2+(4m+n)x+(2n-2m)y+2mn＝2x^2+3xy-2y＋5y-2对应项系数相等所以4m+n=0,2n-2m=5,2mn=-24m+n=0,n=-4m2n-2m=-8m-2m=5-10m=5,m=-1/2,n=-4m=2符...