已知m^2+m-1=0,则m^3+2m^2+2009=
问题描述:
已知m^2+m-1=0,则m^3+2m^2+2009=
答
∵m^2+m-1=0 ∴m^2+m=1 m^3+2m^2+2009 =m^3+m^2+m^2+2009 =m(m^2+m)+m^2+2009 =m+m^2+2009 =1+2009 =2010
已知m^2+m-1=0,则m^3+2m^2+2009=
∵m^2+m-1=0 ∴m^2+m=1 m^3+2m^2+2009 =m^3+m^2+m^2+2009 =m(m^2+m)+m^2+2009 =m+m^2+2009 =1+2009 =2010