Question

$$\sum\limits_{k=-1}^{10}(k^2+k)$$ toplaminin degerini bulunuz.

Answer 1

$k$ yerine $-1$  ve $0$ verirse ifade

 

$0+\sum\limits_{k=1}^{k=10}(k^2+k)$ şeklinde olur.

$=\sum\limits_{k=1}^{k=10}k^2+\sum\limits_{k=1}^{k=10}k$

$=\dfrac{10.11.21}{6} + \dfrac{10.11}{2}$

$=440$ elde edilir...