已知a^2+4a+1=0,且(a^4+ma^2+1)/2a^3+ma^2+2a=3,求m

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已知a^2+4a+1=0,且(a^4+ma^2+1)/2a^3+ma^2+2a=3,求m
已知a^2+4a+1=0,且(a^4+ma^2+1)/2a^3+ma^2+2a=3,求m

已知a^2+4a+1=0,且(a^4+ma^2+1)/2a^3+ma^2+2a=3,求m
a^2=-4a-1
a^3=a^2*a=-4a^2-a=-4(-4a-1)-a=16a+4-a=15a+4
a^4=(a^2)^2=16a^2+8a+1=16(-4a-1)+8a+1=-56a-15
(a^4+ma^2+1)/2a^3+ma^2+2a=3
a^4+ma^2+1=6a^3+3ma^2+6a
2ma^2=-6a^3-6a+a^4+1
-8am-2m=-90a-24-6a-56a-15+1=-152a-38
2m(4a+1)=38(4a+1)
m=19

a^2+1=-4a ==> a^4+2a^2+1=16a^2,==> a^4+1=14a^2
a^4+ma^2+1=(14+m)a^2
2a^3+ma^2+2a=2a(a^2+ma/2+1)=2a*(ma/2-4a)=(m-8)a^2
(a^4+ma^2+1)/(2a^3+ma^2+2a)=(14+m)/(m-8)=3
m=19

(a^4+ma^2+1)/2a^3+ma^2+2a=3 两边同时乘以 2a^3
2ma^5+5a^4-6a^3+ma^2+1=0 把a^2+4a=-1代入得
2ma^5+5a^4-6a^3+ma^2 = a^2+4a 两边同时除于a并整理得
2ma^4+5a^3-6a^2+(m-2)a= 4 把a^2+4a=-1代入得
2ma^4+5a^3-6a^2+(m-2)a=...

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(a^4+ma^2+1)/2a^3+ma^2+2a=3 两边同时乘以 2a^3
2ma^5+5a^4-6a^3+ma^2+1=0 把a^2+4a=-1代入得
2ma^5+5a^4-6a^3+ma^2 = a^2+4a 两边同时除于a并整理得
2ma^4+5a^3-6a^2+(m-2)a= 4 把a^2+4a=-1代入得
2ma^4+5a^3-6a^2+(m-2)a= -4a^2-16a 两边同时除于a并整理得
2ma^3+5a^2-2a=-14-m把a^2+4a=-1代入得
2ma^3+5a^2-2a=(14+m)*(a^2+4a) 两边同时除于a得
2ma^2+5a-2=(14+m)(a+4)
由a^2+4a+1=0可知a=根号3-2,代入即可得m的值

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