问题
填空题
若(x2+mx+n)(x2-2x-3)的乘积中不含x3、x2项,则m=______,n=______.
答案
∵(x2+mx+n)(x2-2x-3)
=x4-2x3-3x2+mx3-2mx2-3mx+nx2-2nx-3n,
=x4+(-2+m)x3+(-3-2m+n)x2+(-3m-2n)x-3n,
∴要使(x2+mx+n)(x2-2x-3)的乘积中不含x3与x2项,
则有
,-2+m=0 -3-2m+n=0
解得
.m=2 n=7
故答案为:2,7.