已知x^2-x-1=0,则-x^3+2x^2+2006=_____.

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/26 23:32:56
已知x^2-x-1=0,则-x^3+2x^2+2006=_____.已知x^2-x-1=0,则-x^3+2x^2+2006=_____.已知x^2-x-1=0,则-x^3+2x^2+2006=____

已知x^2-x-1=0,则-x^3+2x^2+2006=_____.
已知x^2-x-1=0,则-x^3+2x^2+2006=_____.

已知x^2-x-1=0,则-x^3+2x^2+2006=_____.
2007
-x^2(x-2)=y-2006 x^2=x+1
-(x+1)(x-2)=y-2006
-(x^2-x-2)=y-2006
-(x^2-x-1)=y-2007=0
y=2007

x^2-x-1=0
x^2=x+1
-x^3+2x^2+2006
=-x*x^2+2x^2+2006
=-x(x+1)+2x^2+2006
=-x^2-x+2x^2+2006
=x^2-x+2006
=1+2006
=2007