已知x+1/x=2,则x2+1/x2=_.

问题描述:

已知x+

1
x
=2,则x2+
1
x2
=______.

∵x+

1
x
=2,
∴(x+
1
x
2=4,
即x2+2+
1
x2
=4,
解得x2+
1
x2
=2.
故答案为:2.