| 2 | ||
Rozwiąż nierówność f(x+1) < f(x), gdzie f(x) = 1 − | ||
| x−1 |
| 2 | ||
f(x+1) = 1 − | ||
| x |
| 2 | 2 | 2 | 2 | 1 | ||||||
1 − | < 1 − | ⇒ | − | < 0 /:2 ⇒ | < 0 ⇒ | |||||
| x | x − 1 | x − 1 | x | x(x − 1) |
| 2 | 2 | |||
1− | <1− | |||
| x+1−1 | x−1 |
| 2 | 2 | |||
− | <− | |||
| x | x−1 |
| 2 | 2 | ||
> | |||
| x | x−1 |
| 2 | 2 | ||
− | >0 | ||
| x | x−1 |
| 1 | 1 | ||
− | >0 | ||
| x | x−1 |
| x−1−x | |
>0 | |
| x*(x−1 |
| −1 | |
>0⇔x*(x−1)<0⇔x∊(0,1) | |
| x*(x−1) |