| n!*n! | ||
an= | ||
| (2n)! |
| n! | ||
0<an< | ||
| nn |
| n!*n! | 1*2*....*(n−1)*n*n! | ||
= | = | ||
| (2n)! | 12*....*(n−1)*n*(n+1)*.....(n+n) |
| n! | n! | n! | |||
< | = | ||||
| (n+1)*....*(n+n) | n*n*.....*n | nn |
|
| ||||||||||||||
≥ 2n, dlatego 0 ≤ 1/ | ≤ 1/(2n). Wniosek: granica=0. | ||||||||||||||
Basiu gdzies mi znikl ten post gdzie pytalem Cie o sume takiego wyrazenia
(n+1)+(n+2)+(n+3)+ .... +2n
rozpiszse to sobie tak
(n+1)+(n+2)+........+(n+n) = [(1+2+3+,,,,,+n)] + (n+n+n+....n) tak moge ?
to pierwszse wiem ile wynosi a to drugie ?
czy w ogole dobrze to rozpisalem ?
