Tích phân $I=\int\limits_{1}^{e}{{{x}^{3}}{{\ln }^{2}}xdx}$ bằng A. $\frac{5{{e}^{4}}-1}{32}.$ B. $\frac{5{{e}^{4}}+1}{32}.$ C. $-\frac{5{{e}^{4}}-1}{32}.$ D. $\frac{5{{e}^{4}}-2}{32}.$
Đáp án đúng: A Đặt $\left\{ \begin{array}{l}u={{\ln }^{2}}x\\dv={{x}^{3}}dx\end{array} \right.=>\left\{ \begin{array}{l}du=\frac{2\ln x}{x}dx\\v=\frac{{{x}^{4}}}{4}\end{array} \right..$