Sử dụng tính chất ${\int\limits_{a}^{b}{\left\lbrack {f(x) + g(x)} \right\rbrack dx}} = {\int\limits_{a}^{b}{f(x)dx}} + {\int\limits_{a}^{b}{g(x)dx}}$ và ${\int\limits_{a}^{b}{k.f(x)dx}} = k.{\int\limits_{a}^{b}{f(x)dx}}$

$\begin{array}{l} {J = \int\limits_{0}^{2}\left\lbrack {4f(x) - 3} \right\rbrack dx = 4{\int\limits_{0}^{2}{f(x)dx}} - {\int\limits_{0}^{2}{3dx}} = 4.3 - 3x\left| \begin{array}{l} 2 \\ 0 \end{array} \right. = 12 - \left( {3.2 - 3.0} \right) = 6} \\ \end{array}$