Cho hàm số

C

- Hướng dẫn giải

Đáp án C

$u=x+1\Rightarrow du=dx$

$f^{\text{'}}\left(x\right)dx=dv\Rightarrow v=\int f^{\text{'}}\left(x\right)dx=f\left(x\right)$

$$\begin{gathered} I_1={\left.\left(x+1\right).f\left(x\right)\right|}_0^1-\underset{0}{\overset{1}{\int }}f\left(x\right)dx \\ =2.f\left(1\right)-f\left(0\right)-\underset{0}{\overset{1}{\int }}f\left(x\right)dx=8 \\ \Rightarrow \underset{0}{\overset{1}{\int }}f\left(x\right)dx=4-8=-4. \end{gathered}$$