| n2−7n+10 | ||
1.) an = | ||
| √n2+3n+3−√n+2 |
| (n+2)!−n! | ||
2. ) bn = | ||
| (n+2)! + (n−1)! |
| 1 | 1 | 1 | 1 | |||||
3. ) an = | + | + ... + | + | |||||
| n+1 | n+2 | 2n−1 | 2n |
| (n+2)*(n+1)*n!−n!] | ||
bn= | = | |
| [(n+2)(n+1)*n(n−1)!+(n−1)! |
| n! [(n+2)(n+1)−1] | ||
= | = | |
| (n−1)![(n+2)(n+1)*n−1] |
| (n−1)!*n(n2+3n+1) | n3+3n2+n | |||
= | = | |||
| (n−1)![n(n2+3n+2)−1] | n3+3n2+2n−1 |