1.（-1/2)的-2次方×0.125+2009的0次方+|-1|=4×0.125+1+1=2.5 2.x²/（x-1）-1-x=x²/(x-1)-(x+1)(x-1)/(x-1)=(x²-x²+1)/(x-1)=1/(x-1) 3.（1-（2/x+1)²÷x-1/x+1 =1-4/(x+1)²...