已知x2-2009x+1=0,求x2-2008x+2009/x2+1 (x2=x的平方)
问题描述:
已知x2-2009x+1=0,求x2-2008x+2009/x2+1 (x2=x的平方)
答
x²-2009x+1=0
则x²+1=2009x
x²-2008x=x-1
原式=x-1+2009/(2009x)
=x-1+1/x
=(x²-x+1)/x
=(2009x-x)/x
=2008x/x
=2008