lim x-> -1 (x^3 + 1)/(x^2 + x) bằng: -3; -1; 0; 1

* Hướng dẫn giải

Chọn A

$\underset{x\to -1}{\lim }\frac{x^3+1}{x^2+x}=\underset{x\to -1}{\lim }\frac{\left(x+1\right)\left(x^2-x+1\right)}{x\left(x+1\right)}=\underset{x\to -1}{\lim }\frac{x^2-x+1}{x}=-3$