Question

\(T\text{ính}\)\(nhanh\)\(:\)

\(A=-1-2-3-4...-99-100\)

\(\text{Đ}\text{úng}\)\(+\)\(1\)\(tick\)

Answer 1

A = -1 + -2 + -3 + -4 + ... + -99 + -100

    = - ( 1 + 2 +3 + ... + 100) 

    = - 5050

Answer 2

\(...\\ A=-\left(1+2+3+...+100\right)\\ A=-\left(\frac{\left(1+100\right).100}{2}\right)\\ A=-101.50=-5050\)

Chúc bạn học tốt!!!

Answer 3

ý bạn là -1 x -2 x -3 x- 4 x -5 hay -1-2-3-4-5-6-7.....?
 

Answer 4

        \(A=-1-2-3-4-...-99-100\)

=>    \(A=-\left(1+2+3+...+99+100\right)\)

=>    \(A=-\left[\left(1+100\right)\cdot100:2\right]\)

=>    \(A=-\left[101\cdot100:2\right]\)

=>    \(A=-5050\)