1.已知x^2-2x-1=0,求2x^3-3x^2-4x+2的值2.因式分解m^3/9+m+2m^2/3 9a^2-b-b^2-3a

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1.已知x^2-2x-1=0,求2x^3-3x^2-4x+2的值2.因式分解m^3/9+m+2m^2/39a^2-b-b^2-3a1.已知x^2-2x-1=0,求2x^3-3x^2-4x+2的值2.因

1.已知x^2-2x-1=0,求2x^3-3x^2-4x+2的值2.因式分解m^3/9+m+2m^2/3 9a^2-b-b^2-3a
1.已知x^2-2x-1=0,求2x^3-3x^2-4x+2的值
2.因式分解
m^3/9+m+2m^2/3
9a^2-b-b^2-3a

1.已知x^2-2x-1=0,求2x^3-3x^2-4x+2的值2.因式分解m^3/9+m+2m^2/3 9a^2-b-b^2-3a
x^2-2x-1=0
x^2-2x=1
2x^3-3x^2-4x+2
=2x^3-4x^2+x^2-4x+2
=2x(x^2-2x)+x^2-4x+2
=2x+x^2-4x+2
=x^2-2x+2
=1+2
=3
m^3/9+m+2m^2/3
=(1/9)m(m^2+6m+9)
=m(m+3)^2/9
9a^2-b-b^2-3a
=(3a+b)(3a-b)-(3a+b)
=(3a+b)(3a-b-1)