Resposta
$\sum_{k=1}^n k^2 = \frac{n(n + 1)(2n + 1)}{6}$.
Explicação
Similarly, $\sum_{k=1}^n k = \frac{n(n + 1)}{2}$ and $\sum_{k=1}^n k^3 = \left[\frac{n(n + 1)}{2}\right]^2$. These identities frequently appear in sequence problems.
Início / Biblioteca / CSAT (Suneung) essentials: original practice / Flashcard sintético
In CSAT Mathematics, how is the summation formula $\sum_{k=1}^n k^2$ calculated?
Flashcard de estudo do deck CSAT (Suneung) essentials: original practice.