Nếu $\displaystyle\displaystyle\int_0^2f(x)\mathrm{\,d}x=4$ thì $\displaystyle\displaystyle\int_0^2\left[\dfrac{1}{2}f(x)-2\right]\mathrm{\,d}x$ bằng
$0$ | |
$6$ | |
$8$ | |
$-2$ |
Chọn phương án D.
Ta có $\begin{aligned}[t]
\displaystyle\int_0^2\left[\dfrac{1}{2}f(x)-2\right]\mathrm{\,d}x&=\dfrac{1}{2}\int_0^2f(x)\mathrm{\,d}x-\int_0^22\mathrm{\,d}x\\
&=\dfrac{1}{2}\cdot4-2x\bigg|_0^2=-2.
\end{aligned}$