一道简单的七年级数学问题已知m^2+m-1=0,则m^3+2m^2+2004=_______.

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一道简单的七年级数学问题已知m^2+m-1=0,则m^3+2m^2+2004=_______.
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一道简单的七年级数学问题已知m^2+m-1=0,则m^3+2m^2+2004=_______.
一道简单的七年级数学问题
已知m^2+m-1=0,则m^3+2m^2+2004=_______.

一道简单的七年级数学问题已知m^2+m-1=0,则m^3+2m^2+2004=_______.
m^2+m-1=0
m^2+m=1
m^3+2m^2+2004
=(m^3+m^2)+m^2+2004
=m(m^2+m)+m^2+2004
=m+m^2+2004
=1+2004
=2005

太难了

求得M有两个解,代入后得2005

因为m^2+m-1=m(m+1)-1=0
所以m(m+1)=1
故 m^3+2m^2+2004
=m^3+m^2+m^2+2004
=m^2(m+1)+m^2+2004
=m+m^2+2004
=1+2004
=2005