已知m2+m-1=0,n2-n-1=0,求代数式m3+n3+2m2-2n2+2008的值?

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已知m2+m-1=0,n2-n-1=0,求代数式m3+n3+2m2-2n2+2008的值?

已知m2+m-1=0,n2-n-1=0,求代数式m3+n3+2m2-2n2+2008的值?
已知m2+m-1=0,n2-n-1=0,求代数式m3+n3+2m2-2n2+2008的值?

已知m2+m-1=0,n2-n-1=0,求代数式m3+n3+2m2-2n2+2008的值?
m^2+m=1,n^2-n=1
m^3+n^3+2m^2-2n^2+2008
=m(m^2+m)+m^2+n(n^2-n)-n^2+2008
=(m^2+m)-(n^2-n)+2008
=1-1+2008
=2008

m3+n3+2m2-2n2+2008
=m^3+m^2+n^3-n^2+m^2-n^2+2008
=m(m^2+m)+n(n^2-n)+m^2-n^2+2008
=m+n+m^2-n^2+2008
=m^2+m-(n^2-n)+2008
=1-1+2008
=2008

答案是2008
m3+n3+2m2-2n2+2008中
m3+2m2=m2+m=1
n3+2n2=-(n2-n)=-1
仔细看看就明白了