问题
填空题
已知x2-x-1=0,则-x3+2x2+2003的值为______.
答案
∵x2-x-1=0,
∴x2-x=1,
-x3+2x2+2003=-x(x2-x)+x2+2003=x2-x+2003=1+2003=2004.
故填:2004.
已知x2-x-1=0,则-x3+2x2+2003的值为______.
∵x2-x-1=0,
∴x2-x=1,
-x3+2x2+2003=-x(x2-x)+x2+2003=x2-x+2003=1+2003=2004.
故填:2004.