Răspunsuri

2014-11-09T17:25:24+02:00
F(1) = 2*1-1
f(2) = 2*2-1
f(3) = 2*3-1
...
f(100) = 2*100-1

S = f(1)+f(2)+f(3)+...+f(100) = (2*1-1)+(2*2-1)+(2*3-1)+...+(2*100-1) = = 2*1+2*2+2*3+...+2*100-1-1-1-...-1 = 2(1+2+3+...+100)-1*100 = 2* \frac{100*101}{2}  -100 = 100*101-100 = 100(101-1) = 100² = 10000
Imi explici te rog si mie ce inseamna * ?
inseamna ori