Question

先化简，后求值：（x+1分之1+x的平方-1分之x的平方-2x+1）除以x+1分之x-1

Answer 1

[1/(x+1)+(x^2-2x+1)/(x^2-1)]÷（x-1)/(x+1)
=[1/(x+1)+(x-1)^2/(x+1)(x-1)]*(x+1)/(x-1)
=[1/(x+1)+(x-1)/(x+1)]*(x+1)/(x-1)
=[x/(x+1)]*(x+1)/(x-1)
=x/(x-1)

Answer 2

题目出成式子，才好求啊！你这样出题实在看不大明白。