原式=
?x+2?3 x+2
-x(x+2) x?1
=x x+1
?x?1 x+2
-x(x+2) x?1
=x-x x+1
=x x+1
,x2 x+1
∵x2-x-1=0,∴x2=x+1,
则原式=1.
解:(1-3x+2)÷x-1x2+2x-xx+1=(x+2x+2-3x+2)×x(x+1)x-1-xx+1=x-1x+2×x(x+2)x-1-xx+1=x2x+1,
由x2+x-2=0,得x1=1,x2=-2 (舍去),
则原式=x2x+1=12.