Tính tích phân \[I = \mathop \smallint \limits_{ - 1}^1 \frac{{xdx}}{{{x^2} + x + 1}}\]

\[\frac{{\ln 3}}{2} - \frac{\pi }{{2\sqrt 3 }}\]

\[\frac{{\ln 3}}{2} + \frac{\pi }{{2\sqrt 3 }}\]

\[\frac{{\ln 2}}{2} - \frac{\pi }{{2\sqrt 2 }}\]

\[\frac{{\ln 2}}{2} + \frac{\pi }{{2\sqrt 2 }}\]