来自顾玲娟的问题
先化简,再求值(1)(3x-3)/(x^2-1)÷3x/(x+1)-1/(x-1),其中x=2(2)(x^2+2x+1)/(x+2)÷(x^2-1)/(x-1)-1/(x+2),其中x=1/2
先化简,再求值(1)(3x-3)/(x^2-1)÷3x/(x+1)-1/(x-1),其中x=2
(2)(x^2+2x+1)/(x+2)÷(x^2-1)/(x-1)-1/(x+2),其中x=1/2


先化简,再求值(1)(3x-3)/(x^2-1)÷3x/(x+1)-1/(x-1),其中x=2(2)(x^2+2x+1)/(x+2)÷(x^2-1)/(x-1)-1/(x+2),其中x=1/2
先化简,再求值(1)(3x-3)/(x^2-1)÷3x/(x+1)-1/(x-1),其中x=2
(2)(x^2+2x+1)/(x+2)÷(x^2-1)/(x-1)-1/(x+2),其中x=1/2
(3x-3)/(x^2-1)÷3x/(x+1)-1/(x-1)=3(x-1)/(x+1)(x-1)*(x+1)/3x-1/(x-1)=1/x-1/(x-1)=(x-1-x)/x(x-1)=1/x(1-x)=1/[2*(-1)=-1/2(x^2+2x+1)/(x+2)÷(x^2-1)/(x-1)-1/(x+2)=(x+1)^2/(x+2)*(x-1)/(x+1)(x-1)-1/(x+2)=(...