Question

已知m^2+m-1=0,试求代数式m^3+2m^2+2000的值.

Answer 1

由已知,m^2+m-1=0

可得：m^2+m=1

m^3+2m^2+2000

=m^3+m^2+m^2+2000

=m(m^2+m)+m^2+2000

=m+m^2+2000

=2001