Question

4+8+12+....+404=408 va rog foarte mult sa ma ajutati am nevoie mare !!!!!!!!!!!!!!!!!!

Answer 1

dam factor comun   4·1+4·2+4·3+......................4·101=4·(1+2+3+....101)=
4·101·102/2=20604  nu inteleg ce e cu 408?????

Answer 2

$4+8+12+...+404=4(1+2+...+101)=4* \frac{101*102}{2}=2*101*$$*102=202*102=20604$