Răspuns :
3+4+5+6...+100 = 100×101÷2 - 3 = 5050 - 3 = 5047 1+2+3+4.....+129+130 = 130×131÷2 = 8515
3+4+5+...+100=(100×101)/2 - 3=5050-3=5047
1+2+3+...+130=(130×131)/2=8515
1+2+3+...+130=(130×131)/2=8515