Question

[Nguyễn Thanh Loan]

1. Tìm x thuộc  Z:

(x+1) + (x+2) + (x+3) +...+ (x+99) = 0

(x-3) + (x-2) + (x-1)+...+ 10 + 11= 11

Answer 1

[Nguyễn Tuấn Minh]

Cau so 1: Co tat ca 99 so hang

Tong la [(x+1)+(x+99)].99/2=0

(x+1)+(x+99)=0

2x+100=0

2x=-100

x=-50

Cau so 2 hinh nhu thieu de

Answer 2

[HOANG TRUNG KIEN]

ket qua x = -50 nhe ban