Question

calculați 4×0+3+4×1+3+4×2+3+...+4×199+3.​

Answer 1

4(0+1+2+3+4+...+199)+3*200

Folosind suma lui Gauss: 1+2+3+..+n=n*(n+1)/2

$\frac{199 \times 200}{2} = 199 \times 100 = 19900$

4*19900+600=79600+600=80200