Question

Se considera functia f:R-R; f(x)=3x. Sa se calculeze f(1)+f(2)......+ f(10). ??

Answer 1

Inlocuiesti X cu 1, apoi cu 2, cu 3 pana la 10.

F(x)=3x
F(1)=3*1=3
F(2)=3*2=6
F(3)=3*3=9
F(4)=3*4=12
F(5)=3*5=15
F(6)=3*6=18
F(7)=3*7=21
F(8)=3*8=24
F(9)=3*9=27
F(10)=3*10=30
=> 3+6+9+12+15+18+21+24+27+30 = 5*33 = 165