| a2 − b2 | ||
Korzystamy z wzoru a − b = | ||
| a + B |
| 2 n2 + 8 − (2 n2 − 5 n +1) | ||
an = | = | |
| √2 n2 +8 + √2 n2 − 5n +1 |
| 5 n +7 | ||
= | = ( dzielimy licznik i mianownik przez n) | |
| √2n2+8+√2n2−5n +1 |
| 5 + 7n | ||
= | ||
| √2 + 8n2 + √2 − 5n + 1n2 |
| 5 + 0 | 5 | 5√2 | ||||
lim an = | = | = | ||||
| √2 + 0 + √2 − 0 + 0 | 2√2 | 4 |
