Question

Calculati urmatoarele sume: 1+2+3+.......+47+48=

Answer 1

Suma lui Gauss:
S= [(1+48)*48]/2=49*48/2=1176

Answer 2

$\displaystyle 1+2+3+...+47+48= \frac{48(48+1)}{2} = \frac{48 \times 49}{2} = \frac{2352}{2} =1176$