Giải thích các bước giải:
\(\begin{array}{l}
S = \int\limits_{ - 2}^2 {\left| {{x^2} - 5x + 4} \right|dx} \\
= \left| {\int\limits_{ - 2}^1 {\left( {{x^2} - 5x + 4} \right)dx} } \right| + \left| {\int\limits_1^2 {\left( {{x^2} - 5x + 4} \right)dx} } \right|\\
= \left| {\left. {\left( {\dfrac{{{x^3}}}{3} - \dfrac{5}{2}{x^2} + 4x} \right)} \right|_{ - 2}^1} \right| + \left| {\left. {\left( {\dfrac{{{x^3}}}{3} - \dfrac{5}{2}{x^2} + 4x} \right)} \right|_1^2} \right|\\
= \dfrac{{64}}{3}
\end{array}\)
