Question

Tìm các sô nguyên x thỏa mãn và tính tổng kua chug

-11< x-2 <6

Answer 1

\(-11< x-2< 6\)

\(\Rightarrow x-2\in\left\{-10;-9;-8;-7;...;5;6\right\}\)

\(\Rightarrow x\in\left\{-8;-7;-6;-5;7;8\right\}\)

Tổng x bằng:

\(\left(-8\right)+\left(-7\right)+\left(-6\right)+...+7+8\)

\(\Rightarrow\left[\left(-8\right)+8\right]+\left[\left(-7\right)+7\right]+\left[\left(-6\right)+6\right]+...+\left[\left(-3\right)+3\right]+\left[\left(-2\right)+2\right]+\left[\left(-1\right)+1\right]+0\)

\(\Rightarrow0+0+0+...+0+0\)

\(=0\)