Question

Va rog e urgent!!!!!!!!!

Answer 1

Răspuns:

inlocuiesti x cu -14, -13, -12, -11, ...5, 6, 7

f(-14)= 14+1=15   f(-13)=13+1=14  f(-12)=-(-12)+1 =13  f(-11)=11+1=12

f(0)=1  f(1)=0  f(2)=-2+1=-1   f(3)=-3+1=-2  f(4)=-3 f(5)=-4  f(6)=-5   f(7)=-6

f(-14)+ f(-13) +...+ f(7)= 15+14+...-5-6=

(1+2+3+...+15) - (1+2+3+4+5+6)   =      folosim suma Gauss

15*16:2- 6*7:2= 15*8 - 3*7= 120-21= 99