∵x=

1

2- 3

=

2+ 3

(2- 3 )(2+ 3 )

=2+

3

∴当x=2+

3

时，
x²-4x+2=x²-4x+4-2
=（x-2）²-2，
=（2+

3

-2）²-2
=3-2=1．