问题
解答题
先化简，再求值：
|
答案
| 2 |
| x+1 |
| 1 |
| x2-1 |
| x |
| x2-2x+1 |
=
| 2 |
| x+1 |
| 1 |
| (x+1)(x-1) |
| (x-1)2 |
| x |
=
| 2 |
| x+1 |
| x-1 |
| x(x+1) |
=
| 2x |
| x(x+1) |
| x-1 |
| x(x+1) |
=
| 2x-x+1 |
| x(x+1) |
=
| x+1 |
| x(x+1) |
=
| 1 |
| x |
当x=5时，原式=
| 1 |
| x |
| 1 |
| 5 |
搜题请搜索小程序“爱下问搜题”
先化简，再求值：
|
| 2 |
| x+1 |
| 1 |
| x2-1 |
| x |
| x2-2x+1 |
=
| 2 |
| x+1 |
| 1 |
| (x+1)(x-1) |
| (x-1)2 |
| x |
=
| 2 |
| x+1 |
| x-1 |
| x(x+1) |
=
| 2x |
| x(x+1) |
| x-1 |
| x(x+1) |
=
| 2x-x+1 |
| x(x+1) |
=
| x+1 |
| x(x+1) |
=
| 1 |
| x |
当x=5时，原式=
| 1 |
| x |
| 1 |
| 5 |