解
(x-2)/(x²-1)×(x²+2x+1)/(x²-x-2)
=(x-2)/(x-1)(x+1)×(x+1)²/(x-2)(x+1)
=(x-2)/(x-1)(x+1)×(x+1)/(x-2)
=1/(x-1)
令x=0
则原式=1/(0-1)=-1