If $\alpha = 3 \sin ^ { - 1 } \left( \frac { 6 } { 11 } \right)$ and $\beta = 3 \cos ^ { - 1 } \left( \frac { 4 } { 9 } \right)$, where the inverse trigonometric functions take only the principal values, then the correct option(s) is(are)\\
(A) $\quad \cos \beta > 0$\\
(B) $\quad \sin \beta < 0$\\
(C) $\quad \cos ( \alpha + \beta ) > 0$\\
(D) $\quad \cos \alpha < 0$