Cho \(I = \int\limits_0^{ - 1} {x{{(x - 1)}^2}dx} \) khi đặt \(t = - x\) ta có :
A.\(I = - \int\limits_0^1 {t{{(t - 1)}^2}dt} \)
B.\(I = - \int\limits_0^1 {t{{(t + 1)}^2}dt} \)
C.\(I = \int\limits_0^1 {t{{(t - 1)}^2}dt} \)
D.\(I = \int\limits_0^1 {t{{(t + 1)}^2}dt} \)