Câu hỏi: Nếu $\int\limits_{0}^{1}{f\left( x \right)}\text{d}x=4$ thì $\int\limits_{0}^{1}{2f\left( x \right)}\text{d}x$ bằng A. $16$. B. $4$. C. $2$. D. $8$.
$\int\limits_{0}^{1}{2f\left( x \right)}\text{d}x=2\int\limits_{0}^{1}{f\left( x \right)}\text{d}x=2.4=8$.