Nếu \(\int\limits_{a}^{c}{f\left( x \right)dx}=7;\,\int\limits_{b}^{c}{f\left( x \right)}=3\) với \(a < c < b\) thì \(\int\limits_{a}^{b}{f\left( x \right)dx}\) bằng A.4 B.-5 C.-4 D.10
Đáp án đúng: A \(\int\limits_{a}^{b}{f\left( x \right)dx}=\int\limits_{a}^{c}{f\left( x \right)dx}+\int\limits_{c}^{b}{f\left( x \right)dx}=\int\limits_{a}^{c}{f\left( x \right)dx}-\int\limits_{b}^{c}{f\left( x \right)dx}=4\)