Đáp án:

• \( I = \int_1^e \left( x + \frac{2}{x} \ln x \right) \, dx = \left( \frac{x^2}{2} + \ln^2 x \right)_1^e \)

\( = \frac{e^2}{2} + 1 - \frac{1}{2} = \frac{e^2}{2} + \frac{1}{2} \)