Question

S=2+4+6+...+400+402 VA ROG AJUTOR!!!

Answer 1

Suma lui Gauss

S=[(2+402)102]:2=(404*102):2=202*102=20604

Numarul de termeni daca nu sunt consecutivi: (402-2):2+1=101+1=102

Answer 2

$\displaystyle 2+4+6+...+400+402=2(1+2+3+...+201)= \\ \\ =2 \times \frac{201(201+1)}{2} =2 \times \frac{201 \times 202}{2} =\not2 \times \frac{40602}{\not2} =40602$