Suma

Post Reply
andy crisan
Pitagora
Posts: 56
Joined: Sun Dec 28, 2008 5:50 pm
Location: Pitesti

Suma

Post by andy crisan »

Sa se calculeze suma
\( \sum_{k=1}^{n} k\cdot 10^{k} \).

***
Top
User avatar
Laurian Filip
Site Admin
Posts: 344
Joined: Sun Nov 25, 2007 2:34 am
Location: Bucuresti/Arad
Contact:
Contact Laurian Filip

Post by Laurian Filip »

Fie \( S_n=\sum_{k=1}^n k \cdot 10^k \). Calculam \( 10S_n - S_n \) si obtinem suma.
Top
Post Reply

Return to “Clasa a 10-a”