A.\(x = {\pi \over 6} + {{k\pi } \over 3};x = {\pi \over 4} + {{k\pi } \over 2}\)
B.\(x = - {\pi \over 6} + k\pi ;x = {\pi \over 4} + {{k\pi } \over 2}\)
C.\(x = - {\pi \over 6} + {{k2\pi } \over 3};x = - {\pi \over 4} + k\pi \)
D.\(x = {\pi \over 6} + k\pi ;x = {\pi \over 4} + k\pi \)