计算x^2-1分之x^2-2x+1÷(1+x+1分之x-3)
问题描述：
计算x^2-1分之x^2-2x+1÷(1+x+1分之x-3)
答
[(x^2-2x+1)/(x^2-1)]÷[1+(x-3)/(x+1)]
={(x-1)^2/[(x-1)(x+1)]}/[(x+1+x-3)/(x+1)]
=[(x-1)/(x+1)]/[2(x-1)/(x+1)]
=1/2