问题
填空题
已知a2+4a+1=0,且
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答案
∵a2+4a+1=0,∴a2=-4a-1,
=a4+ma2+1 3a3+ma2+3a (-4a-1)2+ma2+1 3a(-4a-1)+ma2+3a
=(16+m)a2+8a+2 (m-12)a2
=(16+m)a2+8a+2 (m-12)(-4a-1)
=
=5,(16+m)(-4a-1)+8a+2 (m-12)(-4a-1)
∴(16+m)(-4a-1)+8a+2=5(m-12)(-4a-1),
原式可化为(16+m)(-4a-1)-5(m-12)(-4a-1)=-8a-2,
即[(16+m)-5(m-12)](-4a-1)=-8a-2,
∵a≠0,
∴(16+m)-5(m-12)=2,
解得m=
.37 2
故答案为
.37 2