Question

Sa se afle suma numerelor naturale de la 3 la 101

Answer 1

3+4+.....+101= (1+2+3+4+........+101)-1-2=[(1+101)x101]/2 -3 =
=(102X101)/2 -3 = 5151-3=5148

Answer 2

Progresie aritmetica cu ratia r=1 si 101-3+1 = 99 termeni, Suma Gauss:
S= 99(3+101):2= 99 x 52 = 5148.
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Succes in continuare!