关于x、y的多项式6mx2+4nxy+2x+2xy-x2+y+4不含二次项，求多项式2m2n+10m-4n+2-2m2n-4m+2n的值．
网友回答
6mx2+4nxy+2x+2xy-x2+y+4=（6m-1）x2+（4n+2）xy+2x+4，
由结果中不含二次项，得到6m-1=0，4n+2=0，即m=16
======以下答案可供参考======
供参考答案1:
∵关于x,y多项式6mx²+4nxy+2x+2xy-x²+y+4不含二次项
6m=14n=-2∴m=1/6
n=-1/2
∴2m²n+10m-4n+2-2m²n-4m+2n
=6m-2n+2
=1+1+2
=4供参考答案2:
6mx²+4nxy+2x+2xy-x²+y+4
=(6m-1)x²+(4n+2)xy+2x+y+4
∵不含有二次项
∴6m-1=0
4n+2=0
∴m=1/6
n=-1/2
2m²n+10m-4n+2-2m²n-4m+2n
=6m-2n+2
=1+1+2
=4供参考答案3:
6mx²+4nxy+2x+2xy-x²+y+4
＝（6m－1）x2+(4n+2)xy+2x+y+4不含二次项，有6m-1=0,4n+2=0
解得m＝1/6，n＝－1/2
多项式2m²n+10m-4n+2-2m²n-4m+2n＝6m－2n＋2
当m＝1/6，n＝－1/2时
原式＝6m－2n＋2＝6×1/6－2×（－1/2）＋2＝4
供参考答案4:
6m-1=0,m=1/6,4nxy+2xy=0,n=-1/2,把这两个值代入所求的代数式即可求出值