Lim - {x^3} + {x^2} + 2021 bằng

Chọn C

Ta có \(\mathop {\lim }\limits_{x \to + \infty } \left( { - {x^3} + {x^2} + 2021} \right) = \mathop {\lim }\limits_{x \to + \infty } \left[ {{x^3}\left( { - 1 + \frac{1}{x} + \frac{{2021}}{{{x^3}}}} \right)} \right] = - \infty \) vì \(\mathop {\lim }\limits_{x \to + \infty } {x^3} = + \infty \) và \(\mathop {\lim }\limits_{x \to + \infty } \left( { - 1 + \frac{1}{x} + \frac{{2021}}{{{x^3}}}} \right) = - 1 < 0\).