Nếu \(\int\limits_{1}^{2}{f\left( x \right)dx=-2}\) và \(\int\limits_{1}^{3}{f\left( x \right)dx=6}\) thì \(\int\limits_{2}^{3}{f\left( x \right)dx}\) bằng

* Hướng dẫn giải

\(6 = \int\limits_1^3 {f\left( x \right){\rm{d}}x \Leftrightarrow 6}  = \int\limits_1^2 {f\left( x \right){\rm{d}}x}  + \int\limits_2^3 {f\left( x \right){\rm{d}}x} \)

\( \Leftrightarrow 6 =  - 2 + \int\limits_2^3 {f\left( x \right){\rm{d}}x} \)

\( \Leftrightarrow \int\limits_2^3 {f\left( x \right){\rm{d}}x}  = 8\)