已知x=2+根号5,求x方-4x+2010的值.

问题描述:

已知x=2+根号5,求x方-4x+2010的值.

x²-4x+2010
=x²-4x+4+2006
=(x-2)²+2006
=(2+√5-2)²+2006
=5+2006
=2011