Question

(6+12+18+24+...+600)²:((3+6+9+12+...+300).(1+2+3+...+100)

Answer 1

(6+12+18+24+...+600)²:((3+6+9+12+...+300).(1+2+3+...+100)=
=6(1+2+...+100)6(1+2+..100):3(1+2+..+100)(1+2+..+100)
=36:3
=12

Answer 2

Suma lui Gauss: 1+2+3+...+n=[n(n+1)]/2 =[6(1+2+3+...100)]²:3(1+2+3+...100)*(1+2+3+...100)= =6²(1+2+3+...100)²:3(1+2+3+...100)²= =36:3= =12