Question

紧急求救!解答数学题,要过程!{1+[1/(a-1)]} {1/[(a^2)-1]}{[(x+2)/(x^2-2x)]-

Answer 1

1.=a/(a-1)×1/[(a+1)(a-1)]=a/[(a+1)(a-1)^2]

2.={(x+2)/[x(x-2)]-(x-1)/(x-2)^2}x/(x-4)=[(x^2-4)-(x^2-x)]/[(x-2)^2(x-4)]=(x-4)/(x-2)^2

3.=1/(x-1)-(x+1)/[(x-1)(x-3)]=-4/[(x-1)(x-3)]

不知道对不对……算得很急……