(Unesp 1991) O conjunto solução de │cos x│ < (1/2)
(Unesp 1991) O conjunto solução de │cos x│ < (1/2), para 0 < x < 2π, é definido por:
A
(π/3) < x < (2π/3) ou (4π/3) < x < (5π/3)
B
(π/6) < x < (5π/6) ou (7π/6) < x < (11π/6)
C
(π/3) < x < (2π/3) e (4π/3) < x < (5π/3)
D
(π/6) < x < (5π/6) e (7π/6) < x < (11π/6)
E
(π/6) < x < (2π/3) ou (4π/3) < x < (11π/6)
