1、
原式=(1+x-1)/(x-1)×(x+1)(x-1)/x
=x/(x-1)×(x+1)(x-1)/x
=x+1
=2+1
=3
2、
原式=(1-x-2)/(x+2)×(x+2)(x-2)/(x+1)²
=-(x+1)/(x+2)×(x+2)(x-2)/(x+1)²
=-(x-2)/(x+1)
=-(3-2)/(3+1)
=-1/4