若x2-13x+1=0,则x2+1x2=( ) A.132 B.169 C.167 D.171
问题描述:
若x2-13x+1=0,则x2+
=( )1 x2
A. 132
B. 169
C. 167
D. 171
答
由x2-13x+1=0得,
x+
=13,1 x
∴x2+
=(x+1 x2
)2-2,1 x
=169-2,
=167.
故选C.