Nếu $\displaystyle\displaystyle\int\limits_{2}^{5}f(x)\mathrm{\,d}x=2$ thì $\displaystyle\displaystyle\int\limits_{2}^{5}3f(x)\mathrm{\,d}x$ bằng
$6$ | |
$3$ | |
$18$ | |
$2$ |
Chọn phương án A.
Ta có $\displaystyle\int\limits_{2}^{5}3f(x)\mathrm{\,d}x=3\displaystyle\int\limits_{2}^{5}f(x)\mathrm{\,d}x=3\cdot2=6$.