已知x+1/x=2,则x2+1/x2=_.
问题描述:
已知x+
=2,则x2+1 x
=______. 1 x2
答
∵x+
=2,1 x
∴(x+
)2=4,1 x
即x2+2+
=4,1 x2
解得x2+
=2.1 x2
故答案为:2.