Cho biết ∫f(x)dx=6,∫g(x)dx=8 . Hãy tính...

Question

Cho biết \(\int _{1}^{5}f\left(x\right)dx=6,\, \,  \int _{1}^{5}g\left(x\right)dx=8\)  . Hãy tính \(\int _{1}^{5}\left[4f\left(x\right)-g\left(x\right)\right]dx\) .

 A. 16.

B. 15.

C. 14.

D. 13.

Answer 1

Chọn A 

 Ta có:
\(\int _{1}^{5}\left[4f\left(x\right)-g\left(x\right)\right]dx =\int _{1}^{5}4f\left(x\right)dx- \int _{1}^{5}g\left(x\right)dx\)

\(=4\int _{1}^{5}f\left(x\right)dx- \int _{1}^{5}g\left(x\right)dx \)

\(=4.6-8=16 \)