| x + 2 | ||
I | I ≥ 3, x ≠ 2 | |
| x − 2 |
| (x2 − x − 1)*I x − 1I | |
≥ 1 | |
| x2 − 1 |
| ( x2 − x − 1)*I x − 1I | ( x −1)*(x + 1) | ||
− | ≥ 0 | ||
| ( x − 1)*(x + 1) | (x −1)*(x +1) |
| x+2 | x+2 | ||
≥3 ∨ − | ≤3 | ||
| x−2 | x−2 |
| x+2 | x+2 | ||
≥3 ∨ − | ≥3 | ||
| x−2 | x−2 |
| (x2−x−1)(x−1) | (x2−x−1)(−x+1) | |||
( | ≥ 1 ∧ x−1≥0) ∨ ( | ≥ 1 ∧ x−1<0) | ||
| x2−1 | x2−1 |
| |x−1| | |x+2| | ||
+ | ≥0 | ||
| x−1 | x+2 |
| −(x−1) | −(x+2) | ||
+ | ≥= | ||
| x−1 | x+2 |
| −(x−1) | x+2 | ||
+ | ≥0 | ||
| x−1 | x+2 |
| x−1 | x+2 | ||
+ | ≥0 | ||
| x−1 | x+2 |
| x−1 | x+2 | −x+1 | x+2 | |||||
( | + | ≥0 ∧ x−1≥0 ∧ x+2≥0) ∨ ( | + | ≥0 ∧ x−1<0 ∧ x+2≥0) ∨ | ||||
| x−1 | x+2 | x−1 | x+2 |
| x−1 | −x−2 | −x+1 | −x−2 | |||||
∨ ( | + | ≥0 ∧ x−1≥0 ∧ x+2<0) ∨ ( | + | ≥0 ∧ x−1<0 ∧ x+2<0) | ||||
| x−1 | x+2 | x−1 | x+2 |