已知a2+4a+1=0,且a4+ma2+13a3+ma2+3a=5,则m=_.
问题描述:
已知a2+4a+1=0,且
=5,则m=______.
a4+ma2+1 3a3+ma2+3a
答
∵a2+4a+1=0,∴a2=-4a-1,a4+ma2+13a3+ma2+3a=(−4a−1)2+ma2+13a(−4a−1)+ma2+3a=(16+m)a2+8a+2(m−12)a2=(16+m)a2+8a+2(m−12)(−4a−1)=(16+m)(−4a−1)+8a+2(m−12)(−4a−1)=5,∴(16+m)(-4a-1)+8a+2=5(...