| (x−2)2 |
| x(x+1) |
| −(x2−4) |
| x+1 |
| 1 |
| x+2 |
=-
| (x−2)2 |
| x(x+1) |
| x+1 |
| (x+2)(x−2) |
| 1 |
| x+2 |
=-
| x−2 |
| x(x+1) |
| 1 |
| x+2 |
=
| 2 |
| x2+2x |
∵x为方程x2+2x-1=0的解，
∴x2+2x=1，
∴原式=2．
| x2−4x+4 |
| x2+x |
| 3 |
| x+1 |
| 1 |
| x+2 |
| (x−2)2 |
| x(x+1) |
| −(x2−4) |
| x+1 |
| 1 |
| x+2 |
| (x−2)2 |
| x(x+1) |
| x+1 |
| (x+2)(x−2) |
| 1 |
| x+2 |
| x−2 |
| x(x+1) |
| 1 |
| x+2 |
| 2 |
| x2+2x |